What brand do you fellas prefer? I picked up some surefire brand, and they have been HORRIBLE, I have a light on my HD weapon and they will last only a few months before running down. That's with almost no use. I can't remember the brand I had before, but they lasted well over a year maybe 18 months before I had to change them. Maybe I got lucky on the other brand or just some old surefire batteries. What say ye OSA?