Confidence trashed by their service agent and manager

My first experience was good after my Audi Dual Clutch gearbox failed. They remanufactured the mechatronic unit. 3 Weeks later I had my car back. 1 Week later it failed again and they replaced the mechatronic unit with a new one. They had to outsource the programming of the TCU because they couldn't get it right. The car returned with a hooter fault which revieled crosswiring from the fuse to the relay and 13A 'leaking' to somewhere unknown. I have just got the run around in them agreeing to analyse and rectify the fault.