I have been using my T10LC2 with AW 18650 battery with great results. The light is extremely bright and will last me an entire 8 hour shift while working over nights. As for the "uglier beam" I cannot really say because I never owned a T10L or the T10C2. I own numerous other lights including a bunch of Surefires and Fenix TK10. The beam has a great hot spot, nice corona, and excellent spill. For duty work its awesome. The throw is also very impressive. Several of the guys that I work with are also very interested. Having the option to use a rechargeable 18650 battery is nice while still keeping the option to use 123 primaries if the 18650 goes down is even better. I may not have all of the technical light knowledge like most of the other folks on this forum but I know what works and what works well! +1 on the T10LC2!