Went thru 275 rounds in break in session.....100 each of 115grn fmj wwb & federal. 75 of remington hollow pts. No failures to fire or eject. Was very pleased with 17 rd and 12 rd flush mags. 12 rd extended-finger mag would not lock back slide with either fmj or hp's. Anyone else have this issue? Prior to break in, I had all 3 mags loaded full for 2 wks to break in mag springs. Gun shoots fricken ragged hole from 7 yds! After session, field strip for cleaning was a breeze.