Ive heard a number of reasons for white boats, most of them are that white boats dont stick out on the starting line.

If you are working with room temp cure epoxy, you need to be careful with it softening above 140 deg F. A dark color surface can get to 160 deg F in the sun on a 100 deg day in Texas.

The HT hulls are vinylester and glass, so I dont believe you have to worry about heat. You could find a resin chemist and ask them if vinylester will soften at or below 160 deg F.

Or you could just keep the hulls covered, or in the shade, or splash them with water before you put them under any stress.

Go for paint, it looks better then gelcoat.

Bill