Like any other piece of defensive kit, you have to train with a weapon-mounted light to use it safely and effectively. To adhere to the sacred muzzle direction safety rule, you have to practice bouncing the light off of surfaces before acquiring your target. How many people do that? Only operators operating operationally. Then again, if you’re truly tactical, you’ll want to hold your light away from your body so as not to provide the bad guys with a target. Then again, if your light’s weapon-mounted, you won’t leave home without it. (Will you?) Then again, you can’t do the up-and-down momentary vertical light sweep (best practice for room clearing) with a weapon-mounted light. I carry a Surefire flashlight. How do you light-up your life?