Your front bumper is also off, and i can't see the rear bumper as to see if it is off, as you said.
The front Bumper should have a wedge like shape protruding out the front. You have this shape, though the top crease that runs along the top (attaching it to the bumper) should run through the Fog lights, and then come to a sharp point at the sides.
Your crease seems to stop before the Fog lights, and then continues after them, creating a awkward crease. That looks like it doesn't belong there.
Also there should be a crease running around the bottom of the bumper. Starting at the wheel well, and heading around slightly, and ending at the start of the wedge.
Also there should be a crease on the top of the bumper, at the side of the Head lights, running around to where the side indicators should be.
Now non of this is too major, and can be fixed with simple tweaking, so theres no real problem.
Also the side skirt on your models runs too far under the car. Set up your bottom ref, and you will see that it only goes, under slightly.
Also the rims are off, they should go in allot deeper. Google some images, and you'll see what i mean.
Anyway, other than that everything looks great to me 
P.S. I sent you an Email with the Paint Shader!
www.stevenegan-cgi.com
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