So Wednesday just gone my car was in at the local dealer for a service and I had them do the NOx update as well.   Engine software version went from 7828 to 9979. DSG software version was unchanged at 3107.   So far I'm very pleased with it. Pickup from low engine speeds (something the DSG is fond of doing) is smoother and cleaner - my guess is better management of the combustion process. It feels torquier at low engine speeds too. No loss of power higher up the rev band that