Its a nice shot, however; it doe's not fit the image of the car. Try a more city look next time. Take a look at Total 911 magazine this month. There are some really nice layouts that show case the car, but they have an edge to them. The background can make or break the image as a whole. That background is more for a Ford full size truck
Try a bit more fill in lighting on the side of the Mustang too. Thats a really sharp color, but it lacks "pop"
A great idea is a long lens shot with the car in the forground and the road running out behind it, gives it a road race feel. A lower view would work well also. Turn the front wheels so they show more of the five spoke look and catch a bit of glint off the polished rim.
Have fun on your next shoot and post up some of the images