This mattress has been giving me back pain for the last three weeks I've been sleeping on it.  It's far too firm for my taste and seems uncomfortable no matter if I'm sleeping on my side or back.  I've been waking up with back pain every day - something I never had before this mattress - and regularly can't fall asleep until 2 in the morning.  The only reason it's two stars instead of three is because the material itself seems of decent quality and hasn't fallen apart or anything - it's just extremely uncomfortable.