Sleep Innovations Marley Hybrid 10 Inch Cooling Gel Memory Foam & Innerspring Mattress - Cal King Size, Medium Firm Support, Bed in a Box for Cool & Comfortable Sleep - Perfect for Hot Sleepers & Back Pain Relief

Update 5-12-19.. had it over 4 years, still my favorite mattress. No issues at all..Update 3-8-18 Still love this mattress. Absolutely no issues to date. No Sagging of any kind.Update: 12-26-16I have had this mattress almost two years now, and I am still super pleased with it. It has stayed constant the entire time. No sagging in the middle what so ever. Still the best mattress I have ever owned, and if for some reason, I would need to buy another, I would in a heartbeat!We are very pleased with our new mattress! We spent a weekend going to many mattress stores and came home very depressed because it was going to cost us 3K to 4K for a new mattress we liked. I did some online research and came across this Sleep Innovations Mattress. It had all of the feature we were looking for, but the price was so low compared to the big name memory foam mattress. After reading the reviews I decided to give it try.. And I am glad I did!It was delivered in two days thanks to Amazon Prime. It was easy to get into the bedroom and set up. I have included a few pictures so you know what to expect. The last picture is after about a hour from the time I opened it. The mattress cover became very tight after about a day. During the set up I didn't have any smell that others have mentioned. I measured the mattress after 48 hours and it was 11 1/4".We waited 24 hrs. to give it a try, and the first thing we both said was "Boy this is firm!" We wanted a firm mattress, but I don't think anything we tried at the stores were even close to this firm. We both sleep well the first night, and have been sleeping even better as we have gotten used to the new mattress. We did change from a traditional pillow top bed mattress, so regardless if we spent big bucks on the name brand, we still would have a learning curve.Now after our first week, and couldn't be happier! I have not had any issues with heat building up, so I am guessing the gel does do what it is supposed to. We have also noticed that we are sleeping much better then we did on the old mattress. This mattress is so comfortable!!!The only thing that I can say that we are sacrificing for this mattress as compared to the Big Name one, it that the material on the Big Name mattress cover does seem to be of a higher quality, which quite frankly has nothing to do with the performance of this mattress. Once the bed is home and the sheets are on it, it was never noticed againAdditionally, this bed is made in the USA!!!