I recently purchased an ex-demo 2012 Audi Q5 with 2-litre diesel engine and S Tronic gearbox from a main dealer. I'm finding the gear changes are very noticeable at low speeds, and that the car feels unresponsive to the throttle when pulling away from stationary, then will surge slightly as the revs pick up. Overall, the drive quality is not as smooth as I would have expected. I was loaned a brand new 2-litre automatic Audi A6 while the Q5 was being checked, and that was beautifully smooth. The dealer assures me that the car drives normally for an S Tronic and that there are no software upgrades applicable, but I would appreciate your thoughts.