It really worked for me so far, I love it. My wife is experiencing some back pain though and it's not for lack of wanting the mattress to work. So I give it a 7 because I don't want to give the impression that this mattress is good for everyone. We're still going to give it more time. We're grateful it's a 100 night trial because we feel it might just take a bit more time for things to adjust.
Because I already recommended Tuft and Needle to a friend. :-) I bought my mattress in the nick of time, right before I ruptured a disc in my back. Recovery couldn't be on a better surface.