The white one (sport) has vertical components at the bottom of the valence and the air dams on each side seem to rest lower. Also the white one has chrome rings around the fogs, ala Mercedes. What do you think?

ich.

Red S-Line (it's not very clear but the S-Line badge is on the front fender where the side turn signal used to be):
<img src="http://gallery.audiworld.com/albums/album373/AU070267_medium.jpg">

White non-S-Line
<img src="http://gallery.audiworld.com/albums/album373/AU070272_medium.jpg">