I have a serpa holster for my Glock 23. I like it. It is a little too bulky to wear under a large shirt, prints too much. I only wear it under a jacket in the winter and at the range. I have heard of a couple instances where some dirt or sand gets caught in the mechanism locks the gun in the rig. This makes it next to impossible to get the gun out without some serious work, so I hope it doesn't happen when I really need it. But to this point this has never happened to me, I also don't go running around it the dirt ans sand though while carrying.