I also find pockets to be really tough on EDC gear - especially things that attach to a keyring. I've had the most problems with USB drives, finally finding the Verbatim TUFF-‘N’-TINY actually holds up well. I've also found the more compact Fox-40 Micro wasn't durable enough so I carry the stronger Fox-40 Classic now (although the Mini looks like it might do the trick too).

I've had two different problems with keychain sized lights; either durability issues or they were too easy to accidently turn on. But I've been carrying a Fenix E01 for about 3 years now and it still works great (of course, this is a AAA light, not a AA one so it doesn't strictly fit what you are looking for).