I know that a lot of new fiberglass boats suffered from blisters. I don't know if they fixed that issue or not. But a few small bumps are not going to slow a boat down noticeably. If you race, that may be another story as you want every advantage you can get.

I have read that a lot of scratches like are so common on Tupperware boats can have a noticeable effect. It just happens slowly so the owner don't notice it. NO first hand experience there.

What I found when I ran the figures on Basic Boat was that at 2 lbs of resistance you lost 1/8 of a mph for every 25 lbs extra.