First, I don't usually right reviews unless I'm extremely dissatisfied or extremely satisfied. it's important to understand that there could be other mattresses out there that would have given me the same result. I don't know and I will probably never find out because I'm NOT buying another mattress brand for a very long time. I bought my mattress in October 2017. The reason why I was interested in a new mattress is because the 2-year 'new' mattress that I had was giving me back problems. They weren't severe back problems but every morning I would have to stretch before leaving the room or even going to take a shower. The pain was gradually getting worse over the course of maybe a year or a little more. Additionally, I had injured my knee playing basketball in late 2016. Considering my age (early 40's), I thought my knee and back pains were mostly due to aging. I figured my body wasn't as capable at repairing itself through the night like it used to. In late 2017 my knee pain was getting much worse to the point where I had to ice it almost daily and had to undergo physical therapy 2-3 times per week. I continued to play basketball on it which didn't help at all (but I love the game...so I'll play until I can't play anymore). Physical therapy would help a little but it would still swell and some days I could barely walk up and down stairs. What does this have to do with the bed? I researched mattress for more than 6 months before deciding on trying Purple. I thought if I could reduce the back problems maybe it would help me isolate the knee issue I had. This is the part were you won't believe what happened and you'll wonder if this is even a real review. It took only one week and my back and knee problems significantly decreased (almost completely gone)! My legs had a very strange, uncomfortable tingling sensation for the first 5 days. I was close to just returning it because it was so uncomfortable. But by the end of the first week, my body had acclimated to the bed and I've been sleeping well ever since. It's been over 3 months now and I absolutely love the bed. I do have some issues side sleeping or sleeping on my stomach on occasion but I think it's because I don't sleep on my side as much and I haven't adjusted to those positions yet. I'm not going to say this bed is for everyone, but for me, it's been life changing! I can play basketball once again at a level I haven't played in 10 years. I can get out of bed and go straight into any activity without doing stretch routines. Almost all of my knee pain has gone away. What's left of the pain is due to the original injury with a small tear in my meniscus. I recommend this bed to anyone! Particularly, if you are athletic, in your late 30's to early 40's and suffer from unexplained back pain every morning, this bed is for you! Just like Purple says, make sure you give yourself time to adjust as you'll likely experience a different kind of pain (or uncomfortable feeling) in the first few days or possibly weeks. And with the 100 days return policy, you can't go wrong! Also, I purchased their pillow and power-base. My wife and I love the power-base! The pillow works for me (not life changing) and doesn't work for my wife (note - the pillow is heavy and shouldn't be used for pillow fighting with your kids; unless you're punishing them for bad grades or not cleaning their room). Thank you Purple for the great product and great customer service!