Getting one of these is not something you will regret. I just unboxed mine and my jaw dropped. The pictures here and other places just do not do it justice.
It truly is beautiful.
The base color is not grey, and in fact on mine, you can barely make out some dunkelgelb and rotbraun underneath the white paint. This is not a whitewash, but a well painted white camouflage which has gotten dirty.
I personally would have gone a little lighter on the rust streaks and the darkness of the dirt on rough metal areas like the weld seams, but the truth is it is a beautiful model and paint job. When I just take it in, it is one of the finest models in my whole collection.
It is not a fantasy paint job, but artistic license was taken on how dirty it would get and the type of dirt (grease and grime and soot rather than mud and dirt)
Mine has definitely driven through some areas with seriously burning diesel engines (looking at you T-34s) and other burning stuff.
I think I mentioned considering toning the darkness down, but I will not unless I win the lottery and get a second.