Go for LED even for high output. The Fenix L1D Cree I edc puts out light comparable to a Surefire E2e in volume & run time with a single AA. They're not cheap but its half the list price of the Surefire. Admittedly some of the cost of the Surefire is in durability but double the price for less output & less run time? The led Surefire has a better output (45 & 14.5hrs) and run time than the 2AA Fenix (40 & 10.5hrs) but its using 2x123 batteries to do it.