Concerning Winnebago rust...We are not as lucky as some. We have a 2004 Winnebago 36G. Love the motorhome, adore the floor plan, but hate the rust! We're the 2nd owner. (presently this '04 coach only has a little over 30,000 miles) Previous owner lived up north and only drove the Winnie to FL every year and back. He appeared to be very picky about the care of the coach and always took it to the Winnebago factory for service. He also kept it stored inside. We bought it in 2011 and unfortunately didn't look under it before purchasing. However, we did notice rust on the propane tank prior, and the dealer repainted it. It is hard to find any metal underneath without rust. Even the wheel wells are rusting.
I've also read other complaints from Winnebago owners about the rust issue. :-(