The only problem I encountered, was that the mounting screw was too large for the hole in the BG. I ended up enlarging the hole with a bigger cobalt drill bit. The screw fit the threads that I cut in the trunion, but again, the hole in the BG was too small.
Once it was enlarged, it fit fine, and the screw was red loc-tited in place during installation.
I know a lot of people have said they've had 100% reliability without a bullet guide in their 5.45, but I hadn't had this experience. I believe that my rifle is now 100% reliable, as it accepts and feeds all of my magazines without issue. Another "side-effect" of the bullet guide is that now all of my magazines fit TIGHT. There is no wobble at all, and when attached, they feel more or less permanently-attached. Also, the magazine release button needed no filing.
Edited by MyGrassIsBlue05, 26 February 2012 - 11:25 AM.