I converted a 2 AA mini-mag to LED using a Nite-Ize kit and I have been happy with it. I did not like how the standard mini-mag bulb would burn out at the time you needed it most, you then needed a back-up light so you could see to replace the bulb. Long-life LED's solved this problem.

Lately I have been using headlamp LEDs and find them even more useful because they are hands-free.

Mike