[Festus2]

I think you may find that you will have to put some type of protection (foam/padding...) at more places than just the downspouts. Everywhere there is some kind of protrusion or corner where the cover touches the RV will be subject to abrasion and tear.

Check places like the corners of your rear bumper, awning catches, roof top antenna, roof top holding tank vents (black tank...), edges of stabilizing jacks, steps, and other places that may not be "sharp" but form some kind of edge. You may be surprised how these kinds of projections can, especially if the cover is moving due to wind, wear holes in it over the course of the winter months.

Old tennis balls also work well over the gutter downspouts.