I'll throw in another vote for the Fenix E01.

I like that its AAA so spares are common and usually on-hand (for my lights, I run all AAAs too). Its also pretty bullet proof and has lasted for over 2 years on my keyring so far.

For wilderness use, I've started moving it from my keyring to a neck lanyard and it works well in that capacity too.
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Victory awaits him who has everything in order — luck, people call it. Defeat is certain for him who has neglected to take the necessary precautions in time; this is called bad luck. Roald Amundsen