Another solid streamlight option - Streamlight TLR-1 HL-X USB Multi-Fuel High Lumen Rail-Mounted Tactical Light

Streamlight are generally my go-to for any kind of light. Our inspection lights at work are all Streamlight, I have a TLR-7 HL-X on my carry pistol and I put this TLR-1 HL-X on a 4.25" 2011 I plan to run for IDPA/USPSA and it's perfectly sized (flush or peeks out just past the muzzle). This light is CRAZY bright and the beam is very focused. I love that I can pull the batteries to charge them without removing the light from the gun.