I would like to see manufacturers locate dash controls where they are visible and usable while driving. Too many motor homes have radios, dash air, and such are down low in the center. Looks nice but tough to use underway.
I have towed my Mazda B4000 pickup 38,000 miles with nothing more than the full width flap on my motor home. I've towed it from west coast to east, over all types of road surface, with no sign of rock chips or dings. It does get dusty when towing on unpaved roads, but I expect any shield would allow dust to accumulate as well.