pattonfrench

Hello everyone. Happy Labor Day! New to the forum and apologize if this has been covered but I've not been able to find anything on point through searching.

I have a 2013 A6 with the 20" sport package and am looking for a winter set up. My buddy is selling his 19" S5 split spoke wheels. Before listing them on CL he offered them to me at a very good price. In any event, I've heard that those wheels may not clear my front brakes and I'm looking for confirmation. Seems odd to me that wheels would clear S5 brakes but not standard A6 brakes. So, couple of questions for the experts:

(1) is it the case that these wheels will have clearance issues, (2) if so, are spacers a good option, (3) will spacers cause any safety, vibration, handling or rubbing or other issues on the A6, (3) what size spacers would you recommend (ideally, something I could use on my summer 20"s for a my ore aggressive look year round), and (5) are there other alternatives that you view as superior? I'm in Denver, so while I know 17-18"s would yield better snow results, I think I'm willing to take the trade off given the moderate snow fall here (believe it or not) and fact that I've survived with all seasons in my BMW 335 for the past 4 seasons.

Any all input is greatly appreciated! Thanks!