I think it would depend on what problem you are having.
Tiffin is very good with service and warranty issues, especially if you go to Red Bay, AL. A lot of what is normally out of warranty will be covered. Just my experience.
2012 Tiffin Phaeton 36QSH Diesel Pusher, TireTraker TPMS, Safe-T-Plus, BrakeMaster, '08 Honda CRV, Protect-a-Tow