I have one mounted on the slide in place of the original rear sight of an AMT Automag ll in .22 WMR and it is great. It cut my group size in half. Even though it is just a .22 mag, the slide still cycles pretty violently and the Burris has held it's zero very well. I have similar sights by Dr Optic and Trueglo mounted on a .357 mag and a S&W 22A and all work very well. They can be a bit of a PITA to get perfectly zeroed because the adjustments are very coarse and touchy, you can expect to spend a full box of ammo getting it sighted in, but once zeroed they stay set. They may not be as fast as open sights for snap shooting but are much faster than a scope and the eye relief is totally noncritical, anywhere from touching your nose out to full arm length. And there is no need to turn them on and off, the hood turns it off and it goes on when the hood is removed. In the field I attach the hood to the holster with a short leather thong so that it pops off when the gun is drawn and it doesn't get lost. When mounted over the rear sight location the gun will still fit many common holsters, perhaps with a bit of leather trimmed away. For me it is the best handgun accessory ever made.
