My wife and I own an Everest.....On the way home today from WORK....I saw a Mountainaire being towed by a very high end F650 T/V.....beautiful rig except the dual double trailer tires were bowing out from either the weight or poor design.....never saw that before and it was the first i've ever seen with dual double wheels on a 5ver.....actually looked scary like it was going to let loose.
Anyway....from every forum i've read...Keystone takes care of its customers like few other R/V mfg's...and the Montana line is a good bet; used or new! More bang for your buck!