The issue I have with the Fenix lights, at least the specific models I researched, is that they do not allow rechargeable LiIon's. I am too cheap to buy primary CR123's, they are just too dang expensive. Although I like the CR123 smaller size, I use 1XAA lights that give me an option of Alkaline, NiMH, or LiIon. Unfortunately, that knocks out the Fenix offerings (no LiIon allowed). My wife and I do use the inexpensive Fenix 1xAAA light on keychains (with an alkaline battery). I forgot the model number, but it's the one that costs $15 or less. This little Fenix replaced our previous ARC 1xAAA's (yeah, an old light, but they were one of the first, if not THE first, 1xAAA keychain lights of good quality).