From my observations, "high-maintenance" usually means low self-esteem if she is hot. And the guys with low self-esteems go for the hot high-maintenance girls to feel better about themselves, but it's one-sided, usually all about her. And if she's only thinking about herself, she's probably more likely to stray.
If you want a relationship that works, go for the girl you are comfortable and compatible with, the one that brings out the best in YOU as well. It's not hard.
Most of all, you shouldn't have to ask letsrun who you should be with. But since you are, I'm going to say go with A, but that's only based on how you have described the girls. "Hotties" are a dime a dozen (if you don't believe me, move to Texas), but looks fade. If you are only thinking about sex, think about how you'll spend the rest of each day together and pick who you would rather spend that time with.