HEY! 
I love you guys,
BUTT NOT THAT WAY!!! 
Y'all leave my back door alone. That's your basic one way valve; You know, "Exit Only!"
Okay, yes, the fogs have a sharp top side cut-off and yes, the lens dispersal pattern is important. But those thing being held as constant, the significant parameters distingushing foglight efficacy are wattage, reflector/lens size and proximity to the ground. I know there is some personal preference regarding color. I am PARTIALLY red/green colorblind. I don't know what role this may play. But one thing that is scientifically measurable, is the greater reflection (blinding) off the whiter (bluer) colored lights. I am not trying to sway anyone's opinion,but anecdotally, for just this one person, amber is definitely preferable. My HID's obviate the need for driving lamps. But as great as they are in the darkness, they are at least that blinding in fog.
How bad do you all think large rectamgular fogs would detract from the look of the truck?
Crude Approximation Below: