I bought a temper pedicure 12 years ago before back surgery and have been very happy ever sense !
A Friend of mine just bought a foam mattress in a box from Sam's Club and It feels the same for 1/4 the price !
We have a sleep number, purchased maybe 8-9 years ago and still love it. We have had to replace the air pump about a year or 2 ago..replaced with a generic one, not a sleep number brand since they are real proud of them..happy with it also. If you buy one, you will think there really is not much too them for what they cost, but is worth it. They have several different upgrades, we sprung for the pillow top whihc I thought made it feel more like a normal mattress when the air pressure was lower. I sleep well most nights.
Can't do the temper-pedic. My back is bad enough that I have to move every 20-30 minutes. In a temper-pedic. yous so "embedded" in the thing it's hard to roll over or turn. I slept on one in a motel once and it was pure hell...
Tempur-Pedic has several different densities of foam to choose from.
If you find a store that has a large selection of models to try out, I'm sure you will find one that you will like. I believe they have a satisfaction guarantee for a few months after purchase.
I had a "Chiropractor Approved" twin-wall double pillow top mattress prior to the Tempur-Pedic. It was great for about the first 3 months. Then it developed a depression wherever you slept. Had to flip & rotate that heavy beast monthly. Never again with the pillow top.
Serta iComfort. Good heavy mattress. There are multiple levels of firmness available, we bought the mid-level. It takes a month to break it in - starts out almost like a sheet of plywood. I have noticed a minimal sag in the middle in four years but it still feels the same as it did after break in. You can only rotate these - flipping is not an option. Probably 1/2 the price of Tempur Pedic. You can buy the mattress only if you like - not required to purchase the set though we did.
I have a sleep number i8 I believe. Was around $3600. They did the analysis at the store when I bought it and said my # was 40. But that is laying on my back. I can't do that. I'm a side sleeper. For that I have it turned up to 100 and it still not hard enough. I won't buy another, but I know a couple other people that have them and love them.