A 17500 puts out 3.7V vs an eneloop's 1.2V, so it's a lot brighter. The only dilemma left is the cost of a charger and batteries. If you use your Logan very frequently, then by all means buy a charger and li-ions. I use a Pila IBC and two AW 17500. Altogether it'll cost you about $80. Compared to the cost of CR123s it will pay for itself many times over. Not to mention the IBC can charge a multitude of cells. I've used mine since 2/07.