Not too long after I bought my 4WD truck and camper, I towed my aluminum boat many miles down a gravel road at highway speed one night. In the morning I was amazed and sickened by the damage to the boat. The plastic trailer lights were gone - just pieces left and the boat itself looked like it'd been beaten with heavy chains. In decades of towing various boats with various vehicles, I've never seen anything like it....so never thought to avoid it. The heavy all weather tires on the truck picked up that gravel and threw it like bullets - even tho' the truck has mudflaps. The mudflaps are now much longer. :-( I'm very sure that an inflatable would have been destroyed. Your situation is almost certainly different, but it's food for thought.
Lar.