I'm always happy to chime in with a contrary opinion, so here goes....

vinylester/polyester is cheaper to be sure, but in my experience it's temperamental with regard to mix ratio and curing conditions (temperature, humidity, etc).

Epoxy on the other hand is tough to screw up. the mix ratios are 1:1 or 2:1 or 5:1 instead of 40:1 for polyester, so you can be off by a little and still be OK. System Three epoxy in particular has given me good results in some really crappy weather conditions, and they sell small-repair kits so you don't need to invest in the full $80 gallon of resin. Of course, you can't apply gelcoat over the repair, but that's a non-factor to me since I hate gelcoat anyway. i can never seem to get the color right.

If you have white hulls, I'd suggest an epoxy repair with a painted finish. the beauty of paint (particularly spraypaint) is that you can feather out the edges to blur the boundary of the repair, which makes color matching less critical.

Either method, it's important to work with a smile on your face. If you're all cranky and frustrated while performing the work, it will show in the final product. cum ba yaaaaaaa....