It depends on which game. Having Mike Matei and Pat the NES Punk would raise the value all, but James Rolfe's signature might. Do you plan on selling it? What's it worth to you? "If you don't care about those three guys clean it off. If you only got it to resell it, maybe keep it on. There are people who would pay more for it if it was signed by them, but others wouldn't. Use your best judgement.