In the last 5 years Ive been through a Sterns & Foster pillowtop, an firm Serta, a Select Comfort, and finally a Seally pillowtop w/memory foam. The only thing I havent tried is the fullmemory foam, and after my Select Comfort experience, I will not buy another non conventional mattress again.
The S&F was too soft, the Serta was too hard, and I must be the only person ever to buy a Select Comfort and hate it.
Luckily for me, my back is one part of my body that has never been damaged. After 10 months on the Select Comfort, I was getting less than 3hrs of sleep a night and waking up in severe pain. No setting would work for longer than a week, and customer service couldnt help me at all. I know this is not the norm for these beds. Most people really like them and I know that many NFL trainers provide them to their players. They are supposed to be incredible, but mine was absolutely terrible after less than a year. I think the one I had was the middle grade model 4000, maybe I needed the pillowtop.
My current bed is a Seally pillowtop that has memory foam in the top. Its a very comfortable bed. Ive only had it fora few months, but Im really happy with it.