Definitely an interesting phenomenon. For the hardcore collector, I could see how it might matter what the original color was. To me, who would just want to drive the car, I would care more about what color it is at present. Color, to me, is not something inherent to the car, it is like clothing, and can be changed at will. Engine swaps are a little different, especially as there were often other factory upgrades on cars that have the better engine. (ie, the current SRT-8)