Its cheap, its large, its bright, and it works - Leapers UTG CQB LED Light w/ 400 Lumens

First, this is a cheap light. Compare it to all of your Streamlights and Surefires, its cheap. If you're considering it, you don't want to pay a lot. But its not garbage. Thats the $15 stuff you see on Ebay. Its heavy (buy a more expensive option). The controls are stiff (buy a more expensive option). Does it work, yes. Its very bright, its rugged or at least seems so. The mount is bulky. It has two mid sections. One like a rail attachment, one like a regular flashlight. I've never used the endcap switch so I can't comment. I rarely have it on a gun. It sits in the safe until I hear an armadillo in the woods and I put it on and go outside. Its a good, bright, less expensive alternative to something that would cost you 3X as much.