303 Protectant or Nu Finish for Smooth Fiberglass RV Finish?

Between the two products in OP, Nu Finish is far superior to 303, for use on the smooth fiberglass. While the 303 will give a temporary shine, it will be gone very quickly, just using a damp cloth, followed by a dry microfiber towel. I do use the 303 on my decals, which helps, but will not save them from the sun indefinitely.

Jerry