Heh, you can go to
www.candlepowerforums.com and beat this thread to death....
But my $0.02:
While on duty and off duty, I
always have a Surefire M2 with me, a Streamlight Stinger on my duty belt as well, a Streamlight Ultrastinger in the car.
My M2 has the P61 (120 lumen) lamp assembly in it, which with the low price on 123 batteries now, its great.
The way I see it, especially since my life depends on all my gear, not just a gun, is that, a maglight is like a Hipoint or maybe at best a raven, whereas a Surefire is like a Glock, HK, Sig.
The same way you would not buy bullets that would be ruined by cold weather, you shouldn't have a flashlight that has batteries that are junk in cold weather. (alkaline, nicds, nimhs, etc), lithium is not affected.
But in all reality, if my life is going to depend on it, or also in my case, the life of others constantly, I will only buy and use the best...Because I cannot imagine thinking to myself "what if I had just spent the extra $20"
These days with the prices of the G2 and the lithium 123 batteries being so affordable, it amazes me that not everyone has tactical flashlights who needs them..