I would much rather have a 2006 model with 40,000 miles. Rentals get used really hard by people that are new to MHs. The warranty sounds fishy. The company may not even be around when you need it.
There are plenty of MHs that barely get used. I do not see the logic of buying a late model one that has been used a lot. I would not buy a gas motorhome with more than about 60k miles, or a diesel with more than about 110-120 k miles.
Motor homes cost a lot. They sit around and all the parts cost some serious money. I would pass on this one.