this is one of my newest jobs !
it took about 1 - 2 hours and i hope you like it :D

http://www.freewebs.com/the-fakers/fakers/Audi%20A8-L%20Vergleich.JPG

Thats ALOT better than your BMW, The tint looks like its been done with a gradient, i think you shuold lighten it up a lil. Your mirror is a lil scetchy. Excelent job on the headlights. Rims are ok.
Overall a good chop 7/10

nice try bro... keep working and refining :) u need to work on ur blending some of ur shadings off alot... and ur rims look off center... ur headlight mod looks funny because u used the smudge tool... work with the healing brush when ur working with paint... its damn near imposible to get a realistic look with the smudge tool