Well, we finally got our sleeper sofa with air mattress into our guest room/office downstairs. It entailed paying someone a reasonably small sum of money to take it apart and move it down there, since it was too large to fit fully assembled, but it was worth it.
It's not the same as a Sleep Number bed, I'm sure, but it's orders of magnitude nicer than a traditional sleeper sofa. The air mattress is built-in and it comes with a pump that inflates it in about 30 seconds. It's pretty easy to adjust the firmness, but only overall (unless one of you is significantly larger than the other, which would, I suppose, shift things a little).
That being said, get a riding lawn mower. And the trailer attachment. Trust me, you won't regret it. Then just buy sleeping pills and you won't notice the mattress.