Actually the 3300RLb serves us very well. Until the little one is to big for the dinette, the unit has 4 individual sleeping areas. The two oldest will probably share for some time, how do you tell one they get the loft over the other. I'm sure as they age they will prefer the sofa/air bed in the future as it has view of the TV.
The upgrade will come when we start getting powered toys...
Thanks for the positive comments.