With LED lights, you pay for color, construction, and efficiency. Brightness anyone can do. But will you get a light that lasts six months, or six years. A light that is a nice white, or even slightly warm (yellowish, but not like an incandescent) or a harsh weird purple or blue that hurts your eyes. Or a light that chews up batteries at a furious rate, but is really only running them half way, or one that gives you even light for several hours, then drops off at a predictable rate. All those factors come with a cost. Brightness can be measured in the first second of a fresh battery and advertised. And its the most subjective of all ratings. I'd go for usability and durability first and foremost. Most lights are bright enough for most uses these days.