I can get the two for the same price, the RS4 only has 10,000 miles which is fine. The Rs4 has more power but does it handle any better than the new s4? with the new drive select package in dynamic, its hard to beat. also do you have to rev it high for the power to kick in with the rs4? does the rs4 have more understeer than the rs4 and is it really worth it to get the rs4. i know its really rare and cooler to own but the s4 is newer and handling is insane. so main questions are: Handling comparison, Power delivery, reliability.
Let me know and share your thoughts.

 

From what I gather the S4 will actually be the quicker car. I have a 2011 S4 and do prefer it over the RS4, the power delivery in the midrange is much better with the supercharger than it is in the NA motor and reliability is really a non issue with either car.

 

Assuming the s4 is the 3.0 supercharged, its probably faster. I would still go RS4 though. Its rarity will hold value better, and its was more badass.