Plan on driving the MDX 10 years, so signed up for the undercoating & rustproofing, as well as the 3M paint protection film on the front end & mirrors.

Undercoating: I was looking underneath when I got it home, just for curiosity, and the underside is covered in black undercoating. Sticky in spots even. These are heavily factory undercoated? If so, dealer is charging me to apply what's already there?

3M: The small panel between grill and hood is a smoother texture than the hood. I can tell from the edge that it's got a protective film on it. That's one of the areas they are applying 3M. So they put film over factory film?

Rustproofing: I just took a quick search of rustproofing and some suggestions are I might be spending useless money there?

Thanks.

 

From Consumer Reports:
Does your car need undercoating: The short answer is no. Cars today are manufactured with corrosion protection, which makes this added treatment unnecessary, though it is profitable for car dealerships. Consumer Reports recommends that car buyers skip the undercoating and several other pricey add-ons, including VIN etching, fabric protection, and extended warranties.