Very nice looking model/textures. I agree with previous post about vibrance, I see very slight blue in shadows and yellows in highlights which could be increased to accentuate the shape...just a suggestion as its all about personal preference
The glass material needs a bit of work, as the interior is coming across as a matte grey in the 3/4 front shot. Is the windshield a closed volume mesh or a plane?
To get some ideas on how to construct specular materials, try out some of the mats in the Live DB and see how they are made.
Also, there is some shadow clipping, all-in-all, very minor details on an excellent piece of work. Keep it up!
Regards,
Ben