Beachgirl,
You mentioned BMW hitch. Is that intended for the rear of the coach? Or, is it a B&W hitch which is a turn-over ball and using a "gooseneck" adapter that fits down over the turn-over ball?
If you are referring to the turn-over ball with a gooseneck adapter, I really advise against those with coachs as heavy as the DRV's are. From what I've been told, those type of adapters put additional strain on the frame of the coach, especially in the front.
Here is a link to a gooseneck adapter on Amazon.
http://www.amazon.com/5th-Wheel-Goos.../dp/B000NDL4TU
Terry