Spacers for OEM Avus Wheels - what size?

[3audis_sofar]

I'm thinking about spacing out my OEM Avus wheels on my B6 S4. Has anyone done this and what thickness looks best? Photos? I'm measuring about 12mm for the rears. Any downside to doing this?

[3audis_sofar]

10mm front/12.5mm rear on this S4. I'm going with 15mm on the rears to get them more flush.

http://i513.photobucket.com/albums/t340/Vintagehamiltons/Misc/wheelspacers.jpg
photo by 04v8s4 on AZ