I'm not talking about raw power here. I want to know who you think is better at disguising themselves as other people. Both of them have been caught on occasion, with Clayface and Batman, and Mystique and Wolverine, but they are both very good masqueraders nonetheless. Who do you think is better?
This is only Clayface and Mystique because at the moment I can't think of any other shape-shifting characters who can change their appearance.