hi guys I'm about to purchase a 4.2 tiptronic and as my 19" from my current A6 aren't wide enough for the flared arches of the 4.2 I'm considering putting some 20" alloys on. Main problem is I don't have unlimited funds so looking for a used set. Question is........ Are any of the Mercedes fitments ok (even the ML with smaller tyres!) as I've seen a few 20" x 8.5" to 10" wide rims about..... I know many have the same 5/112 stud pattern but not sure on how the offset work and what I'd need. If not mercs what about putting a8 20" rims on there? Compatible? Also what size tyres should I be looking at getting and I can keep my eye out....... I don't really want to use spacers and want the arches filled as they should be If this is not possible to do without spending big bucks then I'll hunt down some genuine 19" rs6 alloys. Then again, they won't be cheap! Any advice out there?