My first 2xAA light was a 4Sevens Quark AA2 Tactical. I liked it enough to buy another 2xAA light. Since then I have bought 5 total lights that use the 2xAA format. Of the 5, the Quark is my least favorite. I like the Klarus P2A, Klarus ST20, Jetbeam BA20 and finally the best of the bunch...