OK, I've been swayed and will say no. By nature I don't like to mistrust people without sound evidence for doing so, and I'm still not sure what I have to lose as I'm not sure any misuse by this person would ever take away any legitimate sales I might make anyway, but... the above comments have convinced me to be a hard-nosed skeptic. Doesn't feel good, but it seems like the right decision. Thanks for everyone's input.