Its a fact that an Audi (any Audi for that matter) is set up in a way which makes it quite easy and predictable to drive it on the limit. I also find the Z to be much more of a challenge. I m pretty sure on a twisty road with short and long bends i would be faster in my previous TT, part because I had more experience in it and mostly because the car is so easy/predictable to drive on the limit (read, boring). To give you an idea, we tried for 2 hours to get the tail out on the front wheel drive TT on a skidpad without using the handbrake (you know, weight shifting and all that stuff, slalom around cones to get it going and more of that, with a pro instructor). It went ONCE on those 2 hours, the rest over the time understeer understeer understeer.
The Z keeps you more awake and you for sure need to be much more aware of what you are doing
I like it