I just got an Insight 80 lumen LED light for pictinny rails (spelling?) and I mounted it on my shotgun. It is blinding so I have to say if you were hit with that in the eyes at any distance in a house it would blind you and then allow me to see you better.
Unless you had one pointed at me.
But I am very happy with it and it cost $99 at my local gunshop. It says its unbreakable. That is another test for another day.