Hmm...that's weird. Especially since some peeps are running them with zero issue but you're rubbing. How much material do you have left on your brake pads? (just curious)
From the pics in this thread, I see there is quite a big step on the inner lip of the barrel:
http://www.e90post.com/forums/showthread.php?t=690978
I take it, that's where you're rubbing?