I feel I should add a bit to this. I don't have experience with Rhino on an RV, but I did have Rhino Liner applied to our pickup bed when it was new. The precise function and intent of the products may be different, as may be the chemical composition, I don't know.
What I can witness to is the drastic color fading or chalking. This occured uniformly, including places where there was never any wear from use. Plus, the truck has spent 98% of its life in a garage, unexposed to much UV light. Such discoloration may not be a big deal on a roof, as long as the eventual chalking doesn't cause runs down the sides. I'm not sure what may ultimately happen color-wise on the front cap application to Peter and Connie's coach.
That said, the chemical composition of Rhino applied on the cap and roof may be entirely different than that for a pickup bed, its original design intent years ago. Jeff may have applied a UV controlling clearcoat or something as well. I'm just saying the color on the lower cap may not be permanently stable. Any commentary disspelling that possibility will be welcome.
Joel