I would keep the known before jumping into the unknown for a long trip but our Jayco is getting long in the tooth also.
Personally I would look for a shorter upgrade. We prefer Fed, State, and local parks and length makes a big difference in availability and choice. Ours is 38, and just changing the length in the search to 35 or even 30 makes a huge difference. Just check the pics to make sure that there are no rear obstructions like fences or trees. Our rear overhang is 9' or so. You may have to park your tow vehicle in overflow.
There are lots of folks that travel with huge units so it can be done. It's just a personal choice for me, I've been looking for a 32 to 35.
