I have heard of people saying that rail-mounted laser lights like the TLR-4 cause the G19 to fail to eject rounds properly so I thought I would give a report of my experience thus far. This weekend I shot 100 rds total at an outdoor range with 124 gr Winchester white box and 115 gr American Eagles. First of all, the brightness of the TLR-4 was disappointing. I knew it would be dim because it was such a bright sunny afternoon but I could not even see the red dot past 8 or 10 feet. (Maybe that's the norm but this is my first laser.) I decided to leave the TLR-4 on even thought I would be using my regular sights just to see if it caused the Glock any performance problems. I did not experience the first problem with the Glock even though the TLR-4 was attached. I brought a flathead screwdriver in case of a stove pipe but never had to take it out of the backpack. I have tried a slightly different grip that seems a little firmer and it seemed that I had fewer brass ejecting at 6:00 but I will continue to experiment. Nonetheless, that makes 350 rds through my G19 bought a few weeks ago and no real problems yet. Now, as to the TLR-4, hopefully the range owner will let me shoot it at dusk so I can see how it performs and get it zeroed in at my preferred distance.