LuckyDan,
Overall, the FWC is a better built, higher quality unit than the Jayco.
I do like the layout in the Jayco. The windows are at a height you can actually see out. So, it feels less claustrophobic. The weight of both campers, with options, is very similar. However, the Jayco is better balanced front to back and side to side. My FWC was an older 80's model with the cabinets, water, and propane all on the drivers side rear. The camper listed badly, even on an F350. It needed airbags just to level the ride. I suspect the newer FWC are better balanced.
The FWC, like all aluminum framed RV's, has condensation issues in high humidity environments (beach camping). The Jayco is much better in this regard.
I like the popup mechanism in both campers. The Jayco's permits windows and screens all the way around.
I get the impression that Jayco's are strictly lower end units. Mine was assembled with virtually no caulk or sealant. It is a miracle it survived 16 years in Western Washington before I got it. I paid $1200 to have every seam resealed and recaulked. The RV dealer claims to have lost his butt on the deal.
Both my popups were smaller campers designed for Rangers,Tacomas, etc. It would be nice to have one that actually fits a full size bed without sacrificing interior room and storage space.
I bounced both campers down some rough 4x4 roads. So far, the Jayco is holding up ok. The FWC did great.