As others have said the TH20 is a great single AA headlamp. I find this statement somewhat at odds with my own experience. Moonlight is my most used setting when in the field. When my eyes are dark adapted I need very little illumination to see what I'm doing and blasting with high just blinds me. My personal experience around others is pretty similar. I know people who thru-hiked with nothing more than a Photonlight or similar that tops out around 5 lumens. I almost never see someone using 500+ settings around camp. Why would you fiddle with the settings? You pick one sub-setting for L/M/H & leave it. That gives you three modes that have been customized to fit your needs.