Respectfully disagree about the tint difference, I have beam shots of two GT’s, one in warm white and one in cool white, illuminating a water tower in a light rain at 1.9 miles. The cool white is brighter and lights up the tower better in spite of the rain… and I had my wife shining the lights while I went closer to the tower for pictures of the illumination factor. With me 600 yds from the tower the cool white showed brighter and clearer and the pictures clearly showed it.
Fog lights work to undercut heavy fog because they have a flat beam that is focused close to the car. The Amber color is more to not distract oncoming drivers than anything… point them up for distance like your headlights and you will still see a wall of fog, just a different color wall.
The primary reason we see a difference between warm and cool is that the warm emitters are lower powered, thus they illuminate fog or smoke less than a higher powered cool white beam. This is my take on the ~1000 lights I’ve built. YMMV
This will always be an argument because we all see slightly differently, we all use lights to our own advantage as compared to how others use them, so just remember that any advise, including mine, is more relevant to that opinion than to what YOU might do with a flashlight. 
I personally would love the White Flat in the new K1 but it’s pencil beam is not as desirable as a broader more powerful beam so I will go with the XHP-35 HI. Of course I have a lot of lights so slotting a new one between what I have is becoming more difficult. 