you got it:

the $10 E01 is almost as bombproof, puts out a useable 5 lumens or so, and an excellent buy, even if the beam is kinda nasty in color.

for a somewhat brighter 30-lumen light i like the $20 single-stage Fenix E05 (not so much the 3-level 2014 E05 edition).

fact is, i've had hundreds of AAA lights and eventually the chinese-made multilevels die when least expected, so carry a few of them.

i do have a bunch of single-stage Ultrafire E05 that put out 150 lumens on an alkaline AAA. available from DealExtreme www.dx.com/p/ultrafire-e05-cree-xp-e-r5-150lm-1-mode-white-flashlight-black-1-x-aaa-13445 for around $14, they made a great EDC light for city use where you need greater power to override the ambient light than we do here in the wilderness. in terms of quality, about one in ten of them are dead when i receive them, so definitely buy three to be sure you get a couple that work. and then plan on one failing after a while. :-)

but honestly, if you desire a super tough keychain light, then you should buy a custom (mako, spinner, arc Ti, sapphire, killer, et al) or a standard older arc if you can find one.

but if that's just too much money, then buy consumer 'lights in quantity.