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Diamond mattress is a family run mattress company that has been in operation since 1946. Their big differentiator is that they actually make their own pocket coils and process their own memory foam. This is a bit different than many mid-tier mattress companies that outsource their manufacturing. Their specialty is pocket coil and innerspring mattresses, though they also build memory foam mattresses as well. Most customers like their Diamond mattresses, but there were some that had issues with durability and initial feel.
King Koil is a mattress brand that was founded in 1898. It started selling innerspring mattresses, but over the years has expanded to foam mattresses as well. You can find King Koil mattresses across the globe in local retailers. Some of their mattress models may be advertised under other names. Overall, they make comfortable mattresses in a variety of pricepoints, but some may find more value for the materials in other brands.
Based on our aggregated reviews and our scoring method, we recommend both Diamond and King Koil in this match up!
With data from customers, you can more accurately choose the right mattress. However, there are a lot of other brands out there competing for your attention. Customers report feeling both positively and negatively about these mattresses. Some are cozy in their new mattress, but others have complaints about the feel.
Being supported by your mattress is intrinsic to having a good night's sleep. These mattresses do well supporting sleepers at first, but there are some complaints about supportiveness over the long term. Make sure to take a look at the reviews to make sure these mattresses work for you.
Most reviewers find edge support to be a differentiator of leading mattresses. These mattresses are okay in terms of edge support, but there may be more declining edges over time.
Bowling Ball & Density Tests
In tests that measure the density and supportiveness of these mattresses, supportiveness for these mattresses is fairly even. That said, there are some that have experienced issues with support over time.
Good craftsmanship, materials, and quality control will more than likely lead to good durability. Those that don't put a focus on these things may have some complaints from sleepers. When it comes to these mattresses, they get mixed reviews from customers on durability. Some report finding lasting comfort, while others complain about discomfort over the short term. Double-check the reviews before buying.
Some customers are very comfortable with these mattresses., but others are not so sure and have had mixed experiences. Although most reviewers were pleased, some had warnings. Research more below for information on the specifics.
Mattresses that are supportive are sometimes thought to be firm, but when we talk about support, we talk about deep support of the spine, hips, and shoulders. These mattresses are well rated at giving support to the average sleeper, but rarely, there are some that don't find it as supportive as they would like.
Most reviewers describe these mattresses as having good edge support, which ideal for those that sit on the side of the bed or like to lie towards the sides of the mattress.
Bowling Ball & Density Tests
The bowling ball test of even support is important to figure out if the mattress will provide a good surface to support the spine. These mattresses provide a good amount of support for the average sleeper, but some folks rarely may experience some discomfort.
A mattress that has good longevity can save you thousands. Sadly, in this day and age, everything from bedding to clothes degrades faster. These mattresses, specifically, have mixed ratings when it comes to longevity. Each mattress is different in how it affects you individually and may feel comfortable for you for years, but others have reported not being so lucky. Make sure to read more about these before purchasing.
Not as good quality as I was expecting, but you get what you pay for.View More Reviews
I can't complain about this bed -- I am really happy with it and it feels comfortable to me. The only annoyance was that the shipping was late getting to me.
I've had a diamond for a couple years and it is definitely an okay bed. My hubby likes it more than I do. I want something more luxurious.
My last three beds are diamond beds. Their longevity isn't as good anymore, but I still love their products and stand by them as a good bed!
My bed started falling apart after only 3 months. It feels as if you are sleeping in a valley 10'' deep. We are not heavy people. After 9 months on the bed, we couldn't take it anymore.
We had two prior Diamond mattresses that we loved so we thought that we should get a third. We finally found a place with one and that is when the problems started. After only a month, it started to sag. It was like sleeping in a gutter. I called and they sent an inspector who said it was a 7/8 sag, which is within the normal range. The problem was when you get on it, it sags way worse. Sure, I am 200lbs and 6 foot, but my wife is the only 100lbs and the same thing was happening to her!
Purchased the Ethos latex mattress 6 months ago. At first it seemed comfortable, but after 2 months we couldn't sleep on it. We rotated it but nothing helped. Every morning I woke up in terrible back pain. Then I found out that the latex wasn't even latex. 80% polyurethane foam, 6% rayon & 14% latex! This seems like blatant fraud to me as this was very expensive and we thought we were buying pure latex. Very dissappointing.
I love soft beds and this one cradles me into a cocoon every night. I absolutey love the way it feels and think it is perfect if someone loves soft mattresses.
Maybe it is too soft for me because I feel like it is taking my body some getting used to. But the materials seem to be high quality so I am hoping that my body adjusts.
Just doesn't feel right for me. Luckily I was able to send it back right away and the customer service was good.
I am finally sleeping through the night again. I had an awful spring mattress and so happy that I opted to get a new latex bed.
I have purchased four mattresses from them over the years and am getting ready to purchase a new one. Not that the others need replacing, they are still in great shape, they were left behind in a move unfortunately. Dollar for dollar you won't find a better mattress anywhere. They are incredibly fast as well.
HORRIBLE place. I called and spoke with a salesman 2 days before I went in because their store is about an hour away from where I live. I told them exactly what I needed (I needed a custom mattress for my RV). They gave me prices of 2 different mattresses and explained to me the difference. I thought the prices were fair so I showed up and Nick was completely unprofessional. When I told him which bed I was most interested in he quoted me a price almost $250 higher than what I was told just 2 days before. He told me that whoever told me that does not know what they are talking about and he was sorry. I told him sorry does not pay for my gas to get down here. Sorry does give me back the time that I lost. Again he said he was sorry and there was nothing he could do. I even had proof of the prices I was given. When I told him I was going to take my business elsewhere he said "you think you can find a custom mattress for cheaper". I told him I know I can. Later that same day I bought a custom RV mattress 60x72 for $400 including taxes. Plus the mattress I purchased elsewhere was softer, had thicker memory foam, included a cool gel memory foam and had a better warranty. Stay away from these guys. They have no clue what customer service is. The first guy I spoke with on the phone was great but when you get there it is a completely different story. They will jack up the prices at least 35%. Trust me there are better options out there for a custom mattress or a regular sized mattress. You would think getting it directly from the factory would be cheaper but that is definitely NOT the case here.
Don't waste your money on this product they won't stand behind it when it counts. I bought this mattress because the sales person told me they would back this product if there were any problems. Well five years into a twenty five year warranty the side seams have pulled apart and the memory foam has failed badly. they sent out a contracted inspector who;s only job is to deny claims not provide the customer with quality service. Save your hard earned money and buy anything else !
They aren't so helpful with a warranty unless you live there. Don't buy these mattresses outside of Utah because they will tell you to send the mattress to them at your cost THEN they will determine if it qualifies under the warranty and they will "fix it". Then you pay to ship it back to your home, even if it falls under their scope of warranty. Bad customer service!
I've bought over 20 mattresses through the years and my uncle bought hundreds. Ernie is the greatest. Can't believe how he can hoist a mattress on his back and carry it. Hope you are well!
I went here as a kid, the owner is a great guy. The location is the best
I have owned the Ethos – Tranquility Luxury Medium Mattress (Approx. value $2800). Have been very satisfied with the mattress for around 3-4 years. Even though I have owned this mattress since October of 2014. The mattress was delivered to my Southern California residence in Santa Clarita. During the 1st year of purchase. I have only slept on this mattress once or twice for every 60 to 90 day period, It was not until September of 2015, when I have fully moved back from my Northern California address did I sleep on this mattress on a daily basis. So I have really had a good 3-4 year comfort experience before the mattress started to show the deformity. This deformity has resulted in not being able to sleep on my side of the bed due to the sagging of 1.5 to 2.5 inches over approximately 25% of the mattress. This uneven sagging is observable without the need for anyone to sit or even lean on the mattress. About 4 weeks ago I have contacted the reseller from whom I have purchased this mattress and was given the manufacturer contact information. I contacted Diamond Mattress and was required to submit photos and fax over a warranty claim form. Diamond required to send over an inspector to document and process the warranty claim. Diamond Inspector showed up on April 10, 2019 and took more photos and was able to determine that the deformity maybe corrected by replacing the broken bed foundation. The bed foundation was purchased along with the mattress as supplied from the reseller which happens to be original Diamond Mattress foundation. Additionally, when inspecting the mattress the Diamond inspector was able to expose 8-10 inch tear in the mattress stitching (not related to the foundation issue) which was only observable upon turning the mattress bottom up. The inspector said that Diamond Mattress will contact us within a week. On April 18, we heard back from Diamond and were told that even though the warranty would cover the mattress for 10 years, the mattress foundation would not be covered? Asked about the tear in the mattress and he said something along the lines 'we should have reported this issue upon purchase'? I am speechless as to the lack of common sense of that statement with which the Diamond representative insulted our intelligence. How can the Diamond representative assert that the tear in the mattress was already there upon the time the mattress was purchased and delivered? And assuming that was correct, where is the quality control in releasing and shipping a defective mattress and foundation to a consumer? And how many consumers are likely to flip the mattress on its back looking for such a defect? The mattress warranty states that it may be void if the wrong type of foundation is used. However, even when Diamond has supplied their own foundation, Diamond Mattress would not honor their warranty. My experience has demonstrated that Diamond Mattress Warranty is a lie. Diamond should have stood by their product and I should have been provided with a non-defective foundation for this very expensive mattress set. Bottom line close to $2800 investment in this mattress set which is really only worth to me less than $1000. Effectively, when I have purchased the Diamond Mattress product, I have lost close to $2000. My recommendation to anyone who does not want to go through a similar experience D o N o t B u y a D i a m o n d M a t t r e s s
I purchased a Diamond mattress (Spinal Comfort) and paid more than I would have because of the 'Forever Warranty' feature sold me. I recently filed a claim because the upper portion (pillow top) is sagging. Diamond Mattress sent Integrated Bedding Group and reported 3/4" depressions on both sides, left and right, and the top left has shifted outward 2" in a 64" long area. The report also includes a faint yellow 30" stain. This was a pee stain from my baby. John, Diamond Mattress Warranty, said the stain voids my warranty. I explained it is a faint stain on the right side and the pillow top of the mattress is sagging on the left with a length of 64". This does not make sense. There is definitely a defect in materials and/or workmanship. FOREVER WARRANTY IS NOT TRUE. DO NOT FALL FOR THIS FEATURE.
I bought a Diamond Sleep Princess Pillow Top Mattress last Fall and was really looking forward to finally getting a good night's sleep. I got it home and set up and while it was ok at first, within the first three months it started sagging in the middle and has only gotten worse. Maybe I should've chosen a slightly firmer mattress, but all I know is for the money I paid, I'm very disappointed in the quality of this mattress and will never buy this brand again.
This mattress is comfy! It's not too firm and not too soft. I love it! I was a little nervous before I bought it because the price is so low. Once I went in the store and tested it out, I knew I was going to get my monies worth. Granted I've only had it for about a week now, even my boyfriend has confirmed it's super comfortale. Get it while it's on sale.View More Reviews
I bought the twin mattress and much to my dismay there was about a 4 inch gap between the mattress and my bed frame. After measuring the mattress I realized it was only 36 inches wide, not the standard of 39 inches (despite the website listing it as 39 inches wide). I finally got a hold of the manufacturer and they said that their twins are "intended" to be 38 inches wide but that each one can differ by up to two inches. So you're basically left with a mini-twin. I will be returning this.
It's pretty comfy for the price but honestly I could have gotten cheaper at another matress store, definitely shop around more. It's not very thick and the euro top seems like it will be flattened very easily I give it maybe a year before it starts losing its comfort completely
My first set of guests found this to be very comfortable. I slept in the guest room to try it out and found it very comfortable. I am very pleased with this purchase and will purchase future items.
Nice product at the right price. My child needed a mattress for a new college apartment. We saw many options and even ran into a manufacturers rep at the store who helped us with good advice. As usual, the experience was great
love this mattress very comfortable the never disappoint
Great price and such an amazing mattress. The level of comfort is undeniable. I'm very happy with this product and would recommend it in a heartbeat.
This mattress was purchased for a bedroom that is only used for guests and when child is home from college. The mattress is very comfortable and the price is perfect for this situation. We have had it about a week and my kid loves it, it's 12:20 pm now as I write this review and she is still sleeping.
Buying this mattress was an amazing investment. Such a comfortable bed to sleep on and the service and delivery was very prompt and professional.
Very happy with what I bought slept like a baby. The delivery guys came set it up fast. Very happy with the service.
My husband and I are sleeping so much better since purchasing this mattress. It's not too firm or too soft, so you get support without feeling like you're sleeping on a board.
We love our new Mattress! The comfort and quality is unbelievable and for what we paid for it...we just love it!!
I purchased two of these mattress for my boys, without them being there to try them, and they just love it. They said it's so comfortable that it just conforms to their bodies. Mind you my 15 year old is 262lbs and said the bed is like a giant blanket. So hats off for a great product at a reasonable price...
I recently stayed in a bed in a breakfast in Maine--and loved the mattress I slept on. (I've got neck and shoulder issues to the mattress is often crucial.) I found a similar King Koil mattress and Raymour and Flanigan. The price was right; the delivery was prompt. "For this relief much thanks." Happy with my purchse: feels good!
When choosing a bed we needed a firm mattress with back support for me but yet some cushioning for my husband and the King Koil Perfect Response Elite Lakeside Pillowtop was "the perfect" choice. Very pleased with our decision and we even received next day FREE delivery - very nice!
I love my new mattress -and the service that came with it.
The bed is great. It came when they said it would and the sales person was wonderful in working with our family.
Bought this for my guest bedroom and it was given an A plus By my first guest. She couldn't believe it was a firm mattress. Would highly recommend.
WE NEEDED A FIRM MATTRESS AND THIS IS PERFECT! NOT ONLY IS IT EXACTLY WHAT WE WANTED THE INSTALLATION WAS WONDERFUL. WE NEEDED SLATS FOR SUPPORT AND THE DELIVERING TECHS DID IT ALL WITH NO PROBLEM. SALES PERSON WAS WELL INFORMED AND ANSWERED ALL OF OUR QUESTIONS. FLO L
I have a California King Mattress and it is the best.... I was not sure of down sizing to a Queen Mattress, but I must say that it was the best choice I love the way my body rest and the best part is that my husband and I are know closer....
THE MATTRESS AN BOX SPRING I PURCHASED WAS JUST EXCELLENT. ITS MEETS ALL MY STANDARDS FOR COMFORT .THE SALES PEOPLE WERE JUST GREAT HELPING ME FIND THE RIGHT ONE . I HIGHLY RECOMMEND MY CHOICE.AND THE STORE LOCATION ON CROPSEY AVENUE
It's hard to get out of bed after sleeping on this very comfortable mattress. You look forward to relaxing at the end of the day. I like it very much. Keep in mind, coupled with the box spring, it is very high. Can't go wrong with this one, unless you like it extremely firm. It has the right kind of firm but soft too.
Very happy with our purchase! Bed is comfortable. Not too firm, not too soft. Great quality for a great price!
The mattress is very comfortable. It's the best sleep I've had in a long time. It is a 5 star hotel quality mattress. I'm in love. I must stress that the hubby that works at night and have Insomnia also agreed that his sleep has been much better. Thumb's up.
I absolutely love my new bed. Best experience it's comfortable for my back after I come home from work cause I work 19 hours of the day doing labor and I just needed a new way to sleep. This is one of the most comfortable beds I've ever slept in and I highly recommend it to everyone.
The store was great the product was well priced and it was a convenient purchase. Loved the salesmen [Associate name removed].
This mattress has just enough firmness topped with a pillow top that has just enough softness! The price is perfect and the customer service was out of this world. No one trying to force me to the most expensive products in the store.
I am very much enjoying my new mattress. I was afraid it might be too soft but I'm glad I went with the softer mattress over the more firm mattress. While this is soft, it is still very supportive. This mattress is great quality for a good price.
great mattress sleep like a baby love it so much it is great
Best decision i made for my son he loves his new bed. Raymour and flanigan alway have good quality furniture which last a long time. I know when i shop with them im getting good stuff.
I needed a mattress for my fathers spare bedroom so I had a place to sleep when I visited. I didn't want to spend a lot but I wanted something that was nice and comfortable. This mattress is it! I have slept great when visiting him now and the Sales associate Tom P. in Clifton Park listened to my needs and took care of everything! Thank you Tom!
very comfortable but still with support!! Very happy!!
This mattress was purchased for a guest room and has only been slept on once with a report that is was very comfortable. The salesman was very helpful and polite. The delivery team were very helpful and delivered quite timely
I really like this mattress. It's really comfortable and it feels like I'm sleeping on a cloud.
My old mattress was still in good looking shape, but had outlasted the years I needed an extra firm mattress. My new King Koil plush is so comfortable, I sleep right through the night. Both my husband and I are well pleased with this purchase.
Mattress is unbelievably comfortable. My wife and I love it so much.
So far so good! Great price for the quality. I'll write another review after about a month or so
I am so happy with my purchase. I haven't slept this well in a long time. I definitely Recommend this mattress. The salesman was very knowledgeable and he listened to my needs.
I am very happy with my king coil mattress purchase. In the past I have always bought Sealy's. It is very comfortable and I am happy with it. Also the service at the store and the delivery was very good. I am also very happy with the guarantee on the mattress.
Mattress after the first night of sleep had a indentation in it already. Was or is not as comfortable as I expected.