TrueLarry - You are headed down the right track, the dealer is likely the most important person in the purchase of a RV. It is that salesman/owner that wants your repeat business. I have also found this to be true with Insurance; it is the agent and not the brand name.
As to the extended warranty, I personally would pass on that price. Some people, however, like the security feeling. The majority of your house appliances have already survived the "infant mortality" stage. Likely the most expensive component is the generator followed by the refrigerator, and then the rest (microwave, furnace, water heater, converter/charger, awning, air conditioner, TV, slide mechanism etc.)are in the $500 range or less. It seems to be a little high in price to bet that you will have an expensive component fail between 30 days and 1 year. It probably will not fail during the winter months while in storage. If you suspect a water leak, then have it positive air pressure tested before you take it off the lot. Fixing water leak damage can get expensive.