How much light a particular unit produces is a direct product of voltage and current drain.Obviously the shorter the battery life usually the brighter the light. This is why when you take a 123 a 3 volt cell and stack two of them and discharge it in 1.5 hours you get a lot of light, (and heat). I would go to a police equipment supply store, they usually have a demo stand with all that they carry for you to try out and see what makes you happy before you spend the big bucks. I noticed a limited version of this at a Gander Mountain store, propably have one at Cabellas too.