Oh crap, almost forgot to comment this.
Cleaning is done mostly well, but to me you could used bit more time and effort in little details. Like on the left side of the image, you can see where you cut out the background and modified it. Like a clear line in there. Also the way the red car is there on the side of the blue cars side. Reflections dont really "fade" but they distort along different angles and shapes.
Otherwise good and nice work with making the whole car look like an aggressive streetracer.
Well done and good luck to the comp buddy