For me, it's always more difficult and slightly exposing to play something that's close to yourself. I always like to try to hide, just because I can't stand the way I look. But, I think it's important to change every time and come up with something that's as interesting as it can be, for your characters.
And when somebody knows you well, well there's no comfort like that. And when somebody needs you, well there's no drug like that.