Wow, another neat car in your garage!  The Audi brand has always been something I've considered, comparison with the BMW.  The S-series seems to be similar to the M-brand on a regular BMW.  Is the R-series their full race version (similar to the BMW full M car) ?

Thanks!  Yes, the S series is a sportier version of the A series. Pretty quick with a supercharged V6. I think all around its a super nice car from interior to exterior. But it's still pretty mild mannered in my opinion. The RS series with Audi is the most high performance version of whatever model your considering. The RS5 would be the high performance version of my S5.