If you find you often have a light between your teeth - you need to change how you use a light. seriously, it's a route to illness, un-hygienic, and un-professional. By all means I appreciate the honesty but I hope you also appreciate my honesty suggesting you allow some suggestions to modify your most common flash-light use.
Consider, for example, a Zebralight H501. You can clip it on, or stand it up, or lie it down. Uber handy 'task-light'.
there's a world of difference between 1.5v batteries and 3.7v batteries. An energizer 'lithium' er, well when you read lithium here the l91 is no where close to what most people are talking about.
14500, a rechargable lithium -cobalt cell, is from the sounds of it something you've never seen.
Read batteryuniversity.com before getting these, imho.
The human eye can only perceive logarithmic light differences. So saying 225lumen or 240 lumen no-one could tell the difference and they're both only calculated numbers anyway.
An alkaline battery (a 1.5v cell) only has so much capacity. They struggle with high-power emitters. If you want something bright, you need more power. multiple cells, or more potent chemistry.
To answer your question - the lights with AA's are both the same as far as you'll see. Get whatever fits you best.
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