I haven't seen many C7's which have had this done but there numerous S5's and such which have done it. Obviously their headlights are a little different. I really don't like the marker either but don't think the tinting of it looks that great. I would much rather remove it from the light but obviously that is difficult and tricky to do. The other option would be very expensive replacing them with the Euro lights which only have a silver reflector.
This is the one thing I like about the A7/S7. Their side markers are in the bumper so it is super easy to color match them and be done with it.
I've been sitting on a pair of e-codes to finally get rid of the amber. Maybe I'll get around to installing them this weekend.
get them ON!!! i bought a set of headlights on ebay to play around with. The glue they use on the headlights is crazy. the housing would melt before the glue would. the end result was a messed up headlight but at least it wasn't the pair on my car.