All other factors being equal, white is still the most intense light in the spectrum. The appropriate use of white is something else. For preserving night vision red is better, while both red and green light may wash out some map details in those colours. If I was stomping around in the dark ( I prefer my wiggy's bag over all other gear and exercise anyway) red would be my choice. If I was trying to attract the Goodyear Blimp overhead a nice bright white light would be the choice.