It to put 100 ends through my sub2000 yesterday. Very accurate out of the box at 25 yds. 50 was acceptable as all shots were on the target. I have the glk 22 version and tried 3 kci mags 2 were 15 and one was 31 rnds and used 3 glock mags. Zero issues of any kind! I did experience some cheek slap but not bad. Need to fling another few hundred rounds through it before it really broken in. Already added a rail to the bottom just need to find the grip I want.