Sven & Son 12 Inch Gel Memory Foam Mattress - CertiPUR-US Certified, Medium Firmness, California King Size, Premium US-Made Materials for Back Pain Relief & Pressure Relief | Perfect for Master Bedrooms, Guest Rooms & Luxury Apartments

*7-month update*I've had this bed 7 months now, and if anything it's gotten cozier. I do try to turn it every month or so since I'm a single sleeper and I want to try to make it wear evenly, but it's showing no signs of sinking, indentations from my body, or anything like that. I still keep the mattress protector on it, but I unzipped it a little to let trapped air escape (I know it kinda defeats the purpose). The few uncomfortable nights I've had can totally be blamed on my pillow situation and finding just the right setup for my neck/shoulders. My doctor said I sleep like I'm trying to pitch a baseball. :-PThe bed is still fantastic, and I still love it. I'm so glad I found this brand on Amazon, and I hope they're still around if I ever need another mattress in the future.*Original review*This bed is a riddle wrapped in a mystery inside an enigma (Churchill). (I cannot understand how something so cozy-soft and squishy can still be just the right amount of firm, but it IS.)I ordered this mattress (without the adjustable base) on Friday and it was delivered by UPS the following Friday. I'm happy with the delivery time. I set it up on my platform bed and let it expand for about an hour (it expanded to 13" straight out of the plastic, measured again the next day and it was 14"). Then I sat on it and laid across it. It was heaven. The fabric was beautiful and soft. At first I thought the mattress might be too soft and squishy, but laying on it felt perfect... not too much sinkage (and I'm plus size). I put it in a zippered hypoallergenic mattress protector... and you know how those things trap air? So then you go to sit on the mattress and a huge pocket of air forms? They aren't supposed to change the feel of the mattress, but I slept terribly on this mattress on the first night. I tossed and turned and just could not get comfortable. I woke up with back pain (but I have degenerative disc disease in my cervical and lumbar spine, so it's nothing new). Imo, encasing the mattress in the protector made it feel more firm, however by the second night I had received a long round cervical neck pillow. I didn't use it for my neck though as I thought my lumber region needed it more so I tucked it under my waist for a bit more support and slept with my regular down alternative pillow (because allergies) to support my neck. I also did some neck and back stretching exercises earlier in the day to help align my spine as well. Second night, I slept so well. A full painless eight hours. I did toss and turn a bit because I'm a side sleeper and that's normal for me, but it wasn't enough to fully wake me. I'd turn and get right back to sleep. I think this bed just might be The One!To sum it up, I don't think this bed (or any bed) can cure your pain if you have back issues or problems with spinal alignment. You're still going to have to do a little extra to get your body in alignment, but then when you are in a good position, this bed sure does feel amazing. It's pretty easy to get into and out of as well. I've only had two nights on this bed so far, but I will try to come back and update this review after a few weeks. If there's no update, then just assume the mattress was so perfectly heavenly that I forgot all about coming back to update! Til then, sleep well, align your spine and protect that neck (talking to you... looking down at your phone)!❤️