My zebralight h52w is in my pocket everyday, and if I'm working the headband strap is either in my bag, jacket, or the back pocket of my jeans. I've worked in too many dimly lit environments over the years to go anywhere without it. I hardly ever change the batteries in it, and it's never gotten dim. I even had a battery explode in there during an emergency, and totally forgot about it (sacrilege, I know, but in a real emergency you don't stop to clean out your flashlight, you're just thankful that it's still working). I used it for about a month after that with the burst cell in there, and it was nice and bright the whole time. Nothing about the performance made me think anything was wrong. And thats not because I neglected the light, I was using it for sometimes hours at a time, nearly everyday. When I finally went to swap the leaking cell out the acid had dried, and the light was still doing fine on medium. It cleaned up fine, and it's still working like new. With a light this efficient I don't understand why anyone would strap a 18650 to their forehead.