For reliability, I like the full sized maglite.
Man, I have Mags - a mini, a 3C, a 2D, and a 6D.
They served me well for years, no doubt - and they all still work.
But now they're all sitting without batteries. No way would I stock batteries for them over my Surefire (jeez I almost sound like a commercial, but there's plenty around here to know I'm no shill for them...)