While you're in the store climb up on the bed they have on display and jump up and down on it for a few minutes. Even better if you can get the wife to jump with you at the same time. If it doesn't bounce you up near the ceiling then move over to another display until you find the most bouncy one in the store. That's always worked for me. The bouncier the better.
I thought the Sleep Number was reviewed as just a high dollar adjustable fill air mattress? I bought as Serta Posturpedic Premium last time and it sucks has a dent where I sleep and I only weigh 180.