We just picked up our 2nd Northwood Arctic Fox, a 29 5T which is ~31 feet long, about 4' longer than our old one. Even though it is small by full timer standards, it would easily fill the bill and tows as well as the small one. Northwood builds their own frames and they are legendary for strength. I would at least look at them, a lot of value for the price. Ours was in the mid $40K range, including double pane windows, 5.5KW genset, central vac, king bed and lots of little amenities. Check out their forum at:
http://www.afnash.com/forum.php
Good luck!