I said "memory foam" but I'd never get one. I'm a firm, latex foam mattress kinda person. You really 'sink' into memory foam, and that gets hotter than hell. I like a cooler environment for sleeping. The latex has all the other benefits (vibration isolation, durability, etc.)
They're about twice as expensive as a spring mattress up front, but they'll last for
30 years!! and can be used on a platform bed. I really dislike tall beds.
We've had our
Firm Talalay Latex mattress for 6 years now, and it hasn't changed a micron. We're both lard-asses too, so it has stood up to our combined weight very well.
We're about to upgrade to a king-sized bed, and will be using the same vendor.