I read a lot of reviews before purchasing which were all great but everyone seemed to only have had the mattress for a few weeks. I purchased another mattress and I was just too curious to see what the heck was inside this bad, bad mattress. Great mattress with perfect firmness and supportive sides! While I am only 5' 10" tall, I push the scales at 285lbs. Zinus 12 Inch Support Plus Pocket Spring Hybrid Mattress with Euro Top... Zinus 12 Inch Support Plus Pocket Spring Hybrid Mattress with Euro Top / Extra Firm Feel / More Coils for Durable Support / Pocket Innersprings for Motion Isolation / Bed-in-a-Box, King. Disabling it will result in some disabled or missing features. we tried sleeping at various different orientations but after about a week it starts to sag again. 18% is ideal for a 57 yr old man but carrying that much weight isn't. You've come to the right place. It is very firm and has a soft layer on the top and so far it hasn't "sunk" or have any problems. I do not recommend, I will not ever buy from this company . To calculate the overall star rating and percentage breakdown by star, we don’t use a simple average. I have recommended it to all of our friends and family. Zinus warranty makes it very difficult for the customers and won't accept quality and design flaw. Reviewed in the United States on May 30, 2017. Because it's exceptionally firm, Zinus provides great support for large and heavy sleepers. I bought a queen 10 inch. Reviewed in the United States on October 31, 2017, It started to sag in just a few weeks. I am active in Judo, swimming and cycling so it is a healthy weight at 18% body fat. Reviewed in the United States on August 8, 2017. It's the perfect firmness so my husband's back problems have disappeared. The replacement had the same problems as the initial purchase, but was very saggy in the middle. Apparently it doesn't. ..And neither should you. At first, I thought I felt better but I never had a cessation of the back pain. Unraveled the mattress a few days after it was delivered. Finally, about 2 yrs ago, I broke down and the wife and I bought one of those $2400 beds with each side able to move independently. But I awoke the next morning realizing two things. It was just SO FIRM! I have waited 6 months before writing this review to get a true feel of this mattress. But it came with a noisy sound on bottom edge and support from zinus just don't exist. First of all, let me start off by saying that I am a pretty big guy. I am a 475 lb man, and I am very comfortable on this mattress. WRONG! Let me tell you the things others fail to share in their review. And that's amazing considering I use a CPAP. I ordered this mattress around a year and a half ago, and it has really gone down hill. I try calling them, no one ever picks up. This Sinus bed delivers. we finally had to start visiting the chiropractors with mattress related back issues. I'm 115 lbs and have been the sole user of this. That is the reason i decided to buy this mattress, since i was looking for a firm top that wouldn't sink in a lot when you sit on it. Initially i was happy with it, but it has not even been 2 complete months and the mattress sinks in the middle. This may sound like a made up story but, after just one week of usage. For the past 2 weeks (I waited to confirm that it is really the mattress), I've been waking up with a mid-back pain (which has not happened until recently). Find helpful customer reviews and review ratings for Zinus Support Plus Mattress, King at Amazon.com. 100-Night Trial. Reviewed in the United States on August 26, 2017. I am very disappointed, because I now have to go looking for another mattress after buying this one very recently. It also analyzes reviews to verify trustworthiness. I didn't want to spend alot of $ in case it didn't work out, glad to say that if this mattress lasts 2-3 yrs without issues, it will be one of the best purchases I have ever made. Don't make the same mistake as me and go with the fairly priced option. After almost 2 1/2 years of pain, I finally decided to get rid of it. You can still see all customer reviews for the product. I tried sleeping on different sides of the mattress and frequently wake up through the night. He is 6 feet and I am 5'9. So I started looking for a firm spring mattress on Amazon and researched for about a month before I finally made a decision based on product reviews. I wrote to Amazon, but Amazon referred me over to the manufacturer. Now I will warn you that your body may feel a bit stiff for the first few days since the mattress is so firm. I highly recommend it. Reviewed in the United States on July 28, 2018. As my lifestyle became more sedentary, I began to have an increase in body aches and pains. I cut it open and I noticed immediately that a part of the foam sheet was too short to be covering the whole aria of the mattress. But once your body adjusts to that firmness, you are in heaven. It has foam layers above the main Support plus of iCoil Springs thus enabling one to adjust his or her … This mattress is firm and provides excellent support … Bought this mattress about a month ago and followed all of the instructions (open within 72 hours, let it sit for 48 hour before sleeping on it, etc). It is not comfortable to sleep on as you can always feel it slanting. I will update this review further if there are any new developments. The Zinus 10-Inch Performance Plus, Extra Firm Spring Mattress has earned its reputation as a high performing, comfortable mattress. So, if you're on the fence, I hope this review has pushed you over to the better sleep side. and I am very comfortable on this mattress, Reviewed in the United States on September 24, 2016. I'm glad to report that is not the case. My husband and I are about 450 lbs combined and so far this has been one of the most comfortable beds we have slept on. Spend the money once for the a nicer option. I am extremely happy and satisfied with my purchased and the great deal that I got on this mattress compared to other prices out there. Unless of course you want a poor quality mattress, with a side of crappy customer service. This is definitely "extra firm" and exactly what I was looking for. I LOVE THIS BED!!!!!! After 24 hours, it measured 77*60*11". I knew I had to let it air out and decompress for 48 hours or so, which I did, but it seemed like the coils in the corners never came up.