Maybe you won't have to wax it or overcoat it..... As expensive as it is, it's still seems to be the #1 choice for fiberglass boat peeps. It's what I used on my Hunter Compact-II and it's beautiful.
That said, I just painted an older tent trailer and used the (hard to find in CA) Rustoleum Marine paint
and it went on about as smooth and good looking as the Brightside product @ 1/3 the cost.
I can tell you already, the Briteside is a lot harder to scratch or scuff......
BUT.... lets look at these two trailers over the next 5 years and see the aged results.