Played around last night with the colored and white led light on some of my cat's muddy tracks across a tan counter top. Both red and green seemed better than white, blue,or their combination in highlighting the tracks. I liked the combo of red and green the best.
However, the difference was primarily that those colors were easier on my eye, not that they made the tracks stand out that much better. Still, my eye comfort, and therefore endurance in tracking, is important.
Being able to use any one of the four lights, plus any combination, is an interesting feature of this light.
The switches protrude from the body of the flashlight, meaning they can be accidentally pressed. However they must be pressed down against some resistance and must travel a bit before going on. I have put the light on one the EDC keychain that has my car key and have been carrying it constantly. I found the light on once after carrying it in my pocket. I will have to see if this is a significant problem.
More tests, more reports after a week or so.