I carry a SureFire E2E daily all the time (even daylight). I keep a 4D Maglite in the truck with an Army L-light for general purpose use (comes in handy during storms, power outages, etc). I've always kept the SureFire on me since I once had to clear a house with nothing but a S&W Bodyguard and no light in the middle of the night (was likely to be nothing but the heating system kicking on, but had to check, and the young lady and I were about 30 miles from anywhere). Having sweated off about 10 lbs doing that, I swore never again to be lightless (mine had been in my truck). I shouldn't have had to clear the house by myself, but.......that's life.