ahhh...another person who's found the joys of yellow/amber light /ubbthreads/images/graemlins/cool.gif
I think color is probably a personal preference - even though there are probably some physiological reasons why one color may be "better" than another.
Red for example we know is the correct color not to affect true scotopic night (rods only) vision since the rods are insensitive to wavelengths above about 650nm ie: red.
But for most of us who live in urban enviroments - most of the time we're not in total darkness, and anytime we can see any hint of color - we are NOT using true scotopic (rods only) vision. We're more likely to be using at most mesopic vision (combined rods and cones) or even straining to use photopic (cone) vision.
Under these conditions it's more likely that DIMness is the important factor, and color secondary.
My belief is that yellow tends not to glare/dazzle - since that's the color used in fog lights to be anti-dazzle (when scattered/reflected by white fog), and the prevalent use/availability of anti-glare yellow paper pads.
I seem to see well under yellow/amber light - as it seems to give me good definition and contrast - even at low intensities.
Another advantage for me is that it seems to attract less attrention since yellow/amber is most likely the color of lighting in urban and dim environments.
The main disadvantage of yellow/amber is color rendition - this is the one area where white is superior - but I often find white glares/dazzles my dark adapted eyes and it takes longer for my eyes to recover their sensitivity
Yellow (along with orange and red) LEDs only require 3V source, and have longer runtimes than other shorter wavelength color LEDs.
The CMG Infinity Amber Yellow, I believe, is rated at 41 hours (same as the other colors including the white)
BUT the
Yellow Photons are advertized at 120 hours battery life.
I have not tested the runtime -
but I do know that a yellow Photon does last, since I've had a Yellow Photon II for nearly 5 years - waiting for my EDC yellow Photon Mk.1 on my keyring to wear out - and it just won't!!
Here are a couple of relevant threads regarding light colors:
LED Colors and Vision (pics)
Preserving Night Vision - Colors? 
