thought there might be some interest out there to see a Gen 1 GLock 23 with a Burris FastFire using dove tail universal Glock plate (#410326). It was a cinch to install - just drifted out the rear site with a brass punch. I liked it well enough. It was way off zero out of the box, so with the little driver they provide, I was able to zero it in with relative easy at about 20 yards. It will certainly take some getting use to over iron sights. With the location of the on/off switch, I can pretty easily switch it with my thumb. I find, as others report, you tend to have to need to tilt it down (so to speak) to find the dot.. but the more I did it, the more I could go right to it and find it. It seemed to hold zero, no issues with shock from recoil, held firm on the mount (I used a little lock tite to be safe during install).