hello, I'm a newbie on the forum. I' m on the market  for a Surefire M910a. What is for you the best color for the LEDs (military/tactical use) ?

I've heard that blue is often preferrred. I don't have a 910, but that is also my experience with a small handheld that I have.

Tactically... the LEDs turn on when they get wet and stay that way for several hours so be aware of that when getting a Surefire with LED nav lights.  For convenience, I prefer white LEDs because I hate it when every thing is 2 colors and I cant see the color of signs, wires, etc with non white LEDs.  I had zero problems with my M900 causing loss of night vision, etc that people give for reasons the M900 should be any color other than white.  All the LED colors will make you VERY visable to anyone looking directly at you whne you hit the NAV lights in the front 180 degree hemisphere in front of the weapon light.

I prefer white for the same reason that DevL mentioned.

I like white also

Thanks for your advices. I think I'll go for the white LEDs too...