I did the entire boat. I believe the finish of gelcoat can be every bit as good as the highest quality paint job, but you are 100% accurate in the effort required achieve that finish versus paint. I redid my boat in gelcoat because I didn't feel that "I" could produce a decent looking finish in paint (lack of spraying experience) and with gelcoat I could always sand any runs out.

One interesting note about weights. A gallon of gelcoat weighs about the same as a gallon of paint. I don't know if there is more transfer when spraying gelcoat versus paint due to the viscosity differences. I refinished a Hobie 18 in paint a couple of years ago. At the time I worked for a car dealership that had a bodyshop and paint booths so it was easy to slip the painter a 100 dollar bill and some paint and let him spray it. We used more material on that boat then I used in gelcoat on the Infusion. With the paint we had a sealer, than a primer, the paint, and finally the clear coat.

To be perfectly honest, if I had it to do all over again I would do gelcoat again. I don't have the money to pay a pro and I don't have the skills to do paint myself, at least not at the level to achieve results better than I can with gelcoat. 3-5kg's does suck though.