I buy a lot of stuff on ebay. It is rare to see someone (such as yourself) with so much positive feedback. When I do see someone with huge positives and a few negatives (in your case 1!), I assume the buyers were jerks and/or clueless.

I am sure it bothers you, but I agree with Bill -don't lose any sleep over it. Some people cannot be pleased or are looking to go out of their way to be a pain in the a#@.