If it's a mutually platonic friendship (keyword MUTUAL), and you want nothing more from her than good conversation and friendship then yeah it can have advantages. I've known these 2 short asian girls since high school with no ass or tits at all and we're close like family. To be honest, if I were ever forced to bang one of them, I probably couldn't even get it up. We chill and have fun, I give them advice on guys and they give me advice on girls (GOOD, useful unbiased advice).
If you were trying to get with her and she PUT you in the friendzone (the Robin-Ted Mosby dynamic for all my HIMYM fans), she's as good as useless. And rightfully so, since when a girl you game LJBFs you, it's a soft rejection and she knows it is. If you try to get with one of her friends or a girl you guys meet when out, she will communicate the fact that she put you in the friendzone (whether voluntarily or involuntarily). For instance the conversation will go like this:
Becky (girl you like): "Hey who's that guy you're with? He's cute."
Alison (girl ur LJBF with): "Oh you mean Joe? Yeah hes a real nice guy. He's not my type but I'm sure he'll find a good girl some day. Oh by the way, did you see that guy Mike? He's so hot, do you think he'll let us come over his place tonight?"
And just like that you've been blown out by your own "friend".
Bonus Tip: The best wingwoman to have is a girl who has a slight (but not overt) crush on you. If you get a girl in this sweet spot, I swear she will HUNT you pvssy. This is why PUA books like The Game advise you to go out of your way to make a good impression on your targets friends, because when they like you, your target will REALLY like you. Some of the best long-term Fbuddies and LTRs I've had were by referral from girls like this. You don't have to game them (or escalate, rather), you just have to make it known that you are a really cool guy with options that doesn't want anything from her. Go out of your way to add her on facebook, make her laugh and help her with little stuff (but not too much), and basically make her feel good. You'd be surprised how rare it is for women to find guys like this