Also has anyone replaced the lens with the glass? If so did it make a difference?
Seems like with a clip and glass this would perfect...
A high quality glass lens with AR coating will transmit somewhat more light than the stock plastic lens - five even ten percent more light at a guess.
However, I doubt that naked eye observation could could tell the difference. A lightmeter would show the difference, but the human eye isn't sensitive enough to small variances in illumination.
A removeable pocket clip would be nice, but the XL50 is sort of bulky for EDC clipped into a front pocket, at least for me. Not only is the XL50 longer than most 1AA lights but also fatter.
I can EDC typical 1AA lights fairly comfortably in a back pocket, but not the XL50 because of its bigger diameter.
A belt holster would probably be better for EDC. Brightguy lists three holsters for the XL50:
http://www.brightguy.com/accessory_results.php?Sku=MAGXL50S3016
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