Male, playing as female. When I play a game, I want to immerse myself in that world. Playing as a female is a psychological disconnect, so it's easier to play AS the character instead of WITH that character. Whenever I play a male character, I feel more pressured to basically play as me. Choosing what I'd say, rather than the character I'm trying to build. Female characters don't have that kind of attachment, so role-playing is magnitudes easier.
For me, anyway.