We're half-timing in a 35 right now. I don't think I'd want to go bigger due to handling issues. Some CGs are a little tight now and I think we'd have to skip some of them if we were 40+. We're focused on simplicity because we don't know what to expect. No slideouts and no toad. We pull in, hookup, put the awnings down and we're ready to start drinking. The Canadians that pulled in next door has been screwing around with his fiver for 2 hours now.
What's that extra 10 feet get you anyway? I guess a rear bath with a washer dryer would be cool, but it's just the 2 of us and the washer/dryer combo just takes up some closet space.
My answer may be different in May next year.