I purchased this mattress when I purchased my house 8 years ago. I had been sleeping on a 20 year old spring king size mattress.I have the 12” Green Tea version. King. I am a 36 year old side sleeper who weighs 140 lbs.My wife is a 27 year old side and back sleeper who weighs around 250 lbs.I have the pleasure of being able to tell you how this mattress compares with a Zinus 8” cooling gel mattress and a 10” Green Tea mattress.In the 8 years I have owned this 12” mattress not a lot has changed. It has broken in but not down. It is noticeably less firm than the other mattresses without being considered not firm.There are no lumps, dips, divets or sunken in spots. I would buy it again in a heartbeat. In fact I know 6 other people who have purchased this mattress solely because they house sat my dogs for me while on vacation and slept in my bed.So let’s break it down:I purchased the mattress and it came tightly rolled and compressed in a bag that was in a box. I dragged the box to my spare bedroom and dumped it out. I rolled the plastic with the bed in it out and carefully pulled the plastic away from the mattress before carefully cutting along the seam in a quick motion with a box cutter. It immediately began to inflate. I pulled the plastic complete off and left it on the guest room floor. At the time I had just purchased the house. The carpet was clean and the only other item in the room were 3 moving boxes. I opened the 2 windows in the room. It was spring in SC so about 80 degrees. I left the room and continued to clean and unpack. I checked on the mattress about 6 hours later and it looked fully inflated. The room had a smell. It was very light and smelled like new foam as to be expected. I went along and plucked at the corners which were all still not fully up. Left the room and cleaned. I checked in it again before going to bed that night. The bed looked fully inflated, including the corners. I did not touch it. I went to bed and left it alone until that next night giving it almost a full 48 hours. I dragged my old mattress out of my room that night and leaned it against a wall in the spare room and then with the help of my then girlfriend, took the new mattress and placed it on my bed frame. (Which is an adjustable bed frame. More on that later.) there was no longer a smell. I grabbed my old sheets which fit on it perfectly even though this mattress is 12” and my old one was 6”. Grabbed my comforter and pillows and me, my girlfriend and 35 lb Australian cattle dog Beaux and 6 lb chihuahua Wiggles lay down. Heaven.I was 28 and weighed 115 lbs at that time. I had hurt my back at work tripping over a cord while carrying a heavy load when I was 23. My back had never been the same. For the first time in 5 years I lay on that mattress and no longer felt the pressure in my back. Or the constant searing pain. I do not sink into it. It’s by no means cloud like or marshmallow plush. On a scale of 1-10 with 1 being most firm and wooden plank like and 10 being marshmallow soft where you sink and get trapped this is a 3-4. It relieves pressure points but isn’t hard. I don’t bend when I lay on it but can feel my hip and shoulder go in. I don’t get very hot on it and I’m a very hot, very light restless sleeper. Any movement, light, sound, breathing will wake me up. Basically I’m just really bad at sleeping. It’s very good at not transferring movement so my girlfriend could roll or move and I wouldn’t wake up. When I bought the mattress I also got a waterproof cover because Wiggles was 14 and had seizures. Sometimes he would wet himself during the seizures so the protector could protect the mattress. It doesn’t crinkle and you can’t feel it, but even 8 years later the mattress looks like the day I drug it onto the bed.It bends on an adjustable base but is thick enough that it doesn’t bend all the way. The base also vibrates to massage your back. I can feel it through the mattress as well though it is very dampened.Sexy time is no different on this than with a spring mattress. You don’t sink in, there is less bounce and no squeaky springs.Fast forward to 2020. The pandemic. I am now 34 and weigh 155 lbs. mattress still feels and looks the same even with weight gain. No bumps or lumps and not hot, unless it’s summer but no matter what mattress you have you’re gonna be hot when it’s 106 degrees outside and the ac on your 102 barely insulated house is struggling.My spare room is no longer empty with just 3 boxes. It’s now a whole guest room. And it also has a Zinus bed frame and 10” green tea mattress. 10” compared to 12” is a little bit on the firmer side. Now a 2-3 on that scale from earlier. Still pressure relieving but motion transfers a little more. Beaux was testing it out with me and rolled and I could feel the bed jump. Guests still absolutely love it and talk about buying one. I always take them to my room so they can lay on mine and tell me if they feel a difference. They always end up choosing the 12” and buy it for their home.I have slept on the cooling foam Zinus mattress at 8” at my mother in laws house. It is not noticeably cooler but IS noticeably firmer. A 1.5 on that scale from earlier. Just shy of being a wooden plank. I was stiff the next day and my shoulders and torn back muscle aches. My advice is to go thicker on the mattress no matter your weight. Gives more pressure relief without giving you the sink. My mattress at 12” is by no means not firm but it’s also pressure relieving and not rock like.It’s now October 29th 2022.I’m 36 and weigh 140. Wiggles is no longer with us but the mattress cover and Beaux remain. Stryker the 50 lb Australian cattle dog has joined us. I write this review at 8:09 am, laying on the mattress. I slept for 7.5 hours and have no pains, stiffness or aches. I feel well rested. My wife is slightly snoring and just rolled a little and I barely felt it and only because I was awake to notice. I highly recommend this mattress and will replace it with another one exactly like it at the 10 year mark if it feels like it needs to be replaced. It doesn’t feel any different than the day I bought it now though. Maybe the 12-15 year mark if that’s the case.Sweet dreams and have a good night, y’all.