The basic problem with a light on a gun is....
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That in the dark, we use lights to look at things. All kinds of things. Everything. And not everything should have a loaded gun pointed at it.
There is a lot of discussion/argument about lights on guns, but to me, the bottom line is that they are risky. Professionals train, train, and train some more, the rest of us, mostly, don't.
Something spooked you in the night, you checking things out, light on the gun, now, we all know finger OFF the trigger, but....not everyone follows the rules all the time. And unless you are trained not to, you are going to use that light to look at things, pointing a gun at the same time.
TO me, it just increases the risk of an accident. A light not on the gun is, to me, the way to go.
There are valid arguments both ways, and one can come up with situations favoring each one. You have to decide what is both right, and safest, for your personal situation.