Was thinking about getting a new 5er next year when I turn my truck in. We have a 2006 that I paid cash for about 4 years ago. Looked at new 5ers and what I want will cost me close to 40K out the door. My 2006 TT has never looked so good through my eyes. Now I plan on keeping the current one at least until my son gets out of school where the wife and I would have an extended camping season.
My tank was sagging very bad on my Jayco. I worried the same thing was going to happen so a few years back I added some reinforcement to the brackets. This is the reason I had enclosed underbellies. We don't camp in the winter so I could care less about keeping the tanks warm. I would rather see what is going on down there.