[RoSs_bg2_rox]

Go for the girl. It's useless to let it pass, and when you get in a long term relationship (if indeed that is what this would result in) you learn that your friends kinda take a back seat. This guy obviously just isn't for her, and she likes you, so why let the opportunity pass? You said you would let him pursue her if he wanted, and he said the same. Well if you really would, then surely he really would too. So just go for it.