It simply doesn't work for us. I bought it because we have an old mattress that we thought was causing hip discomfort, but that still persists. It's simply doesn't seem to be a fit for us.
It's comfy and doesn't sink. It softens just enough to be comfortable but not so much that I'm worried I'll touch the floor. The fact that I don't need a box spring or a frame is great because I am moving and don't have a lot of money to spare on those things anyway.