One thing about Gel Coats...they are alot like paint, in that they really vary in hardness from boat to boat, or RV to RV. For instance, in the thread below, I cleaned up the oxidation last summer on this boat with a PC, speed 6, a burgundy
Meguiar's cutting pad, and the
Meguiar's marine cleaner wax. It's hard to know how the gel coat will respond until you do a test spot. By the way, this boat is still oxidation free, so my method worked.
24 foot Crownline deckboat
DuraGloss 501 is another awesome product for removing oxidation in conjunction with a PC and cutting pad, and leaving decent protection.