I shot a box and a half through them yesterday and had my first ever fail to feed in one of my R9s. I did not try in the second one, cause I didn't feel like cleaning them both.
Interestingly, my Kahr PM9, which has also never failed (before yesterday) had a couple problems as well. I bought 1,000 of these because they should work fine in my Springfield EMP and XD9, but I think I will stick to the smaller stuff in the smaller framed guns....