The problem with the Arc AAA was availability -- same with the CMG Infinity; they were good lights if you could get one. I have a few lights of similar design: a Peak AAA, Gerber Infinity (4) and a couple Fenix E01. All are good and have never failed. I keep the Peak AAA in my Mission Wallet. The only failure I've had in any of these lights was due to an alkaline battery that failed before its shelf date -- scratch one Fenix E01, bring in the back-up.

BTW, titanium is beneficial in that if a battery dies, aluminum is toast, Ti handles corrosion much much better.