I just treated mine with a fiberglass restorer & then'coated' it with Turtle Wax 'Ice'. I can't imagine not maintaining the gelcoat on my coach be it on the sides, back end, or roof. Gelcoat is stuff that requires periodic maintenance or else it will go South way sooner than it would otherwise if maintained.
Over the years I've had tremendously good luck with the 'Ice' line on all the gelcoat boats I've owned. Using it from top to bottom now on my coach & will continue to do so.
Remember if you use anything carnabua based on the roof it will not 'seal' the gelcoat & thus it will return to a chalky surface again in relative short order unless you use a sealant. Also something interesting about carnabua I recently learned is that it burns off at a relatively low temp (as in well below the ambient temps most areas of the U.S. see in the summer) so even though many swear by it being the best shine on the planet, if you live anywhere that it gets hot out the stuff will burn off... sometimes within days if it's really hot outside.
YMMV but for me I'm taking the hour or so once or twice a year to apply a coat of sealant on my fiberglass roof.
2015 Itasca 25b Ford E350 V10
