Okay, seriously, it's better to have a girlfriend you can get along with, or one who who has the same interests as you, I should say. Someone who you can really just hang out/listen to music/play games/watch tv with. Sure, love is good, but a relationship shouldn't just be based around it, or it will be misery. Trust me. But if both girls are nice, that can be challenging. But just think about it, because you've known your friend longer than the other girl.
I had to choose before between a long-term friend and someone really nice, but I didn't really know him.