303 Protectant or Nu Finish for Smooth Fiberglass RV Finish?

First buffing and restoring the finish, I sprayed the rubber roof with 303.. Some got on to the side fiberglass finish, and I noted it wiped off clean and left a shiny finish.. I then when ahead and treated the entire outside, and then went to my GMC pickup and treated all the plastic exterior and interior parts.

While I do NOT expect it to last as long as normal RV wax, but it's so easy I can see me doing it 4 times a year.