I had to make the same decision back when I was getting my car. I drove both cars and I felt like the RS5 was fun and looked cool(dealership offered me a fully carbon+black out RS5 sportback) but the steering and suspension could not be compared with M550i. Plus coming from an F Type owner the RS5's exhaust sounds like someone put a wet towel over it. The m550i exhaust sounds amazing once you remove the resonators! I am glad I got the m550i and not the RS5 haha. And you can never go wrong with a V8
