The LRI's are good. But stick with the Fenix E01. AAA batteries are cheaper and easier to get ahold of. The one benefit I can see for the flat lights is that they can easily be used one handed. It's a bit awkward to turn on something like an E01 (with it's twist head) one handed, but it can be done. You just wouldn't want to normally.

I carried an ARC AAA for many years. The ARC is the granddaddy of all these 1xAA lights like the E01. I find myself in need of brighter light at times these days, so now I carry a 4Sevens Quark 1xAA with a 14500 LiIon battery in it. But you really can't go wrong with something like the E01 for your normal EDC light.