I just got this on my gun, but have shot it alot! This thing is fast as all hell. If you get this...YOU DEFINITELY NEED ATLEAST A 12V HOPPER since I have a 9 right now (I couldn't out shoot it w/ my old trigger), but you will easy outshoot a 9v hopper w/this. Until I pick up a 12, I'm going to have to shoot in bursts.
dollars per minute increases.... :(
But besides that...nothing at all that I have noticed yet.
BUy this if you want to shoot really fast :). I'm seriously in shock at how fast I can fire with this thing.