As a rule, I'm not a fan of signatures on guitars, other than the back of the headstock. Having said that, I used to own an old white Kramer guitar signed by all 4 members (at the time) of Van Halen. I sold it when the autographs started to fade pretty badly. The guy who had it signed for me didn't use the Sharpie I gave him and used some random marker. I couldn't find anybody to shoot a clearcoat on it because they didn't know what pen, so they couldn't guarantee they wouldn't destroy the signatures. I wish I still had that one.