Just coming from a M135i auto to an S3. The M135i has launch control. Don't be misled, it's no more than a gimmick and a faff to use, certainly not a basis for your decision. Sport auto mode in the BMW and floor it - standing 1/4 at Santa Pod in an unmodified car in 13s dead. Runs tried by others using the launch control were far slower.
The two cars are as quick as one another, it just comes down to the package you prefer after a decent test drive in the end.
Sent from my iPad using Tapatalk