Although probably not in the same category as a C63S, I've had an interest in the Audi TTRS. Has anyone had any experience driving one? If so, what are your thoughts?

Yes, I have. Back when I still had my RS5, Audi piloted a rental service called Audi on Demand here in San Francisco, and I used it regularly to drive anything from the RS3 to the R8 to see what I wanna replace my RS5 with and I ended up getting an AMG, so perhaps that tells you all. I did like my 12 years with Audi and the B8.5 RS5 was the best, but dynamically Audis just don't live up to their competitors.

The TT RS was neat to drive a few times. Took it on several canyon runs and for being an FWD with partially engaged rear axle it did not do too bad, but it's a very one dimensional drive as Audis often are. Their AWD implementation doesn't leave a lot of room to play. In case of the TT it's basically FWD with a ton of grip. It's just no Cayman, which is what it competes with technically.

For regular driving, though, it's small and somewhat harsh. Its biggest issue is the suspension. Audi's Magna Ride implementation is not very good. Audi uses a single wheel level sensor and a basic suspension controller to adjust all 4 corners together and the result is poor and a main complaint about the TT RS from current owners. There are aftermarket suspension controllers that improve it by factoring in additional inputs, but the TT RS is missing the sensor array that for example AMG Ride Control uses. AMG Ride Control on our cars has individual accelerometers for each wheel, individual wheel level sensors and additional accelerometers to measure all the forces that are acting on the car and then factors in other inputs such as steering angle, yaw, speed etc. and adjusts the damping rate individually at each corner. The difference is very apparent.

As a primary car I wouldn't get a TT RS. Perhaps as a weekend car, but then I again there's the far superior Cayman. The TT as whole was a style icon, but as a sports car it was never really quite there.

great in-depth reply! Appreciate it. I had a Cayman GTS a few years back so you probably answered my TTRS curiosity.

what made you choose the r8 over the mag c63? they're very different cars

I didn't choose the R8 over the C63. As I said, after driving the various RS and R8 models, I chose the C63. As for the R8, I was curious and with the new RS5 having gone softer it might have been a candidate, but yes it's not really an everyday car and the quattro system in the R8 was terrible. Never got the chance to drive the RWD R8, but that's probably what I would have gone for if I had bought one.