I have one in a gun that gives good accuracy.
BUT - it was fitted with no less care and only a little less work than conventional match bushing. I bought the oversize bushing and it was fitted snug to the slide in my FLG's usual way. The ring was ordered to fit the barrel tighter than what Briley recommends and the barrel polished for a smooth close fit. So it works but is not a free ride.
I don't know how much help the drop in version would be. Maybe a lot if your stock bushing is loose.
