Put one on, took it off. It worked well, but made the gun too fat to fit in holsters or to be comfortable just sticking it in my waistband. I also had a problem with the shape of the unit where the battery compartment touched the top of my index finger joint. On recoil, it hit my hand hard enough to cause bleeding after about a dozen shots. I looked at smoothing it out, but there's no way since that's the location of the hold down screw for the battery cover.