After knocking up some temporary 8mm spacers to replicate the offset change fro ET43 to ET35 I cannot see how some A4/S4 Owners are fitting 9 inch+ rims.
The 19x8.5 ET35 in my opinion is as wide as you would want to go on the front. The back seems happy to accommodate more but the front is verging on poking out beyond the arch, which starts to look a touch strange and shouts 'WRONG OFFSET' to me.
There is also no rollback of the arch lip on the front along with an inner liner mounting clip/bolt.
I'm still not convinced that the S4 has the same track as my A4 B8.5, as the S4 certainly seems to have a slightly wider tack when viewed from the rear.
It reminds me of years ago when Ford Fiesta and Escort owners were putting Rostyle wheels on, not realising that the Cortina Offset was the correct one to use and the Capri one wasn't....LOL........