Back when I was in school, my sister used to regularly recommend girls from her friend circle to me. She used to be ever so convinced that this girl would be a totally awesome match for me, etc., etc... However, when the friendship eventually cooled down, which seems to happen quite often with girls that age, her ex-friends of course wouldn't be as recommendable anymore... So my first experiences with friends 'auditing' potential girlfriends isn't that good!
So right now, no, I would never have my potential girlfriends 'screened' by one of my girl friends. I'd only take advice from people that know me very very well (which could be guys, for that matter). One can only have an opinion about someone he knows well...