My personal opinion is, I dont like it, depth seems lost by the use of too many colours, and a lack of precision to many of the components, and the girl looks ill... also not liking the copper base colour, it lacks depth. I personally think that the tank shot in silver or gold, then detailed with black, then covered in a Root beer candy, would look stunning, but I do love monochrome airbrush work.
Technically its superb, artist is a master at thinking ahead

If the owner likes it, then its mission accomplished.

Thom