Not too sure what your debate comment refers to. Can you post back with your pin weight and a couple of weights from the truck and fiver? You know - GVW of truck, GVW of RV, max. GCVW and whatever else you can add. How much does the F350 sag after the weight of the RV is fully on it?
It seems to me that a 2008 F350 is a pretty stout towing vehicle. Maybe not as highly rated as the new breed of trucks yet still a pretty darn competent tow vehicle. How old are the shocks on your truck? What kind of shocks are they? Perhaps just upgrading the shocks will bring about a big improvement in ride quality. Can you post up a picture of the the TV and fiver hitched up? It would be good to be able to see the overall "look" of the setup. Also, do you carry a lot of "stuff" in the box of the F350 in addition to the hitch and RV pin when hitched up?
A lot of questions without much help from me. I guess that personally I need more information about your setup.
Cheers and Best Wishes!
Mike