In evaluating the cost and practicality of improving the Jayco fan, I found the Turbo/Maxx fan
. It's probably not a new idea to many readers here but I didn't know of its existence. It seems like an easy way to upgrade without interfering with the roof seal (and therefore warranty) and it gets you a vent cover in the deal.
I read elsewhere (on this forum?) about Jayco floors being soft in some spots. Readers responded with construction descriptions suggesting Rockwood builds more framing into their walls and floors than does Jayco. I have no objective evidence of that, nor do I know for a fact that it matters. But, if mushy floors are not unusual on Jayco, I'll look elsewhere.
If Jayco's engineered floor design results in a stronger (or a strong as) floor with fewer cross members I'm okay with that in principle, if it actually works. But I have little information one way or another.