Seriously it isn't rocket science. Batteries are very standard in voltage and fairly standard in capacity. LED emitters exist in only a handful of sizes/outputs. If two different manufacturers each use the same Cree emitter, put it in a 17mm reflector and power it with 3X AAA... you aren't going to get 250 lumens out of one and only 50 out of the other. I don't have to own a Bell light to know how it does. I own an Ascent 4x AAA headlight. Actually I own three of them, they are that cheap. They remain on the bikes that I ride as backups and the MagicShine gets moved to the bike that is actually being ridden. Before I got the MagicShine I would gang two of the Ascents together sometimes... ... you know... its ok not to know that it gets better than 100 lumens and you don't have to do unspeakable things with your body in sketchy parts of town to get the money... what is sad is that some want to dismiss out of hand anything more useful than what they've got going. A lockblock is a nifty piece of kit but it is not superior to an O-ring for sheer speed and economy. BTW just so you all don't think I drink Geomorange juice for breakfast, I have to observe that anyone can put a P7 emitter in an aluminum housing that is ~2?mm in diameter, power it with 2x 18650 for voltage and 2x more for runtime, contract with a Chinese factory for a low MSRP, and, voila, a (ersatz) MagicShine. I think Gemini lights are like that. MagicShine happens to be what I used specifically to get enough light to see with at night at a price point that I was comfortable with. YMMDV.

H