I switched from Pathogen to Vundle, at the prodding of people on HN, and I can't say I am all that thrilled about the difference. It basically does what Pathogen does, plus it does a bit more. The issue is that the "bit more" that it does just doesn't seem... polished.. to me, and covers things that I never found troublesome to do manually anyway. I'm not going to switch back (since it does what Pathogen does there isn't a reason), but I don't think it is better, just different.