You have the 1.8T in your A4 correct?
It's actually a different turbo :P
The turbos in the 2.7TT are smaller and more high performance. They're both model K03 though.
But anyway, the turbos don't fail from how you drive them - anything over 2.5k rpm, the turbo will be spooled to its maximum stable rpm. That's just how turbo's work