I use it about 80% for street driving, the only times I really turn it off are stop/start traffic and on the motorway. On a S it makes heel & toeing much easier, I find, as the throttle response is much faster. I had a 2.7 loaner car for a week last week without SC and found the throttle response seemed a bit faster than my S with SC off, so I'm not sure I would be as bothered on the 2.7. It's a good option, definitely glad I got it.