My partner and I have been sleeping on this mattress for just over a month now, and we both very happy with it. We are overweight people and both suffer from the long term effects of previous lower back injuries, yet we have found that our quality of sleep has improved massively. I don't wake up during the night with hip and shoulder discomfort any more, and have also found that if I go to sleep on this mattress with an aching back, it has mostly healed by the morning. I used to buy cheap mattresses to save money, but I do think that I have been converted to buying higher quality ones like this one in the future.
I will say that the super-king size mattress mattress is heavy and was an absolute nightmare to get up our narrow staircase due to the size and rigidity of it (we weren't offered delivery to a room of our choice due to Covid restrictions) so I would recommend bearing this in mind if you're infirm, live on your own, or live in a small house like ours. However, it was totally worth the headache!