Top stuff as always. Almost perfect model, great fun physics too.
Only thing I noticed was (on the defaul skin, never tried any others) that the 2 little vents on the back of the roof look a little scruffy (relative to the rest). I think its mostly a UV map issue, as the dark parts don't seem to line up properly. Otherwise its perfect.
Also, I'm in love with the tyre textures/shaders, if you ever want to make a tutorial I'd be forever grateful! :P
Also Cheeveer below might be surprised to learn its not making a single KG of downforce! :P