I have a Surefire M2 Centurion. I also Have the red lens tip off filter, the spares carrier, and the hurricane storn lantern. I keep it loaded with the P61 lamp. It is amazingly bright. Its great because after the run starts to dim, you take the used battery and put them in the hurricane lantern where you can use the last juice out of the batteries before you chuck em. Te light is amazingly blinding. Ive done tests, and during a fully lit house the person doesn't just close his eyes when shone with the light, they actually turn their body away giving you those few cruicial seconds to eith close the distance between you or run depending on your situation. I can't give it high enough praise. Go order it from 1sks and support the forums, kevin has a good price for it. get the accessories i mentioned also (you may not need the red filter, i hardly use it) but i reccomend you get the lanyard, im planning on buying it soon.