I have the SC+ button on at least 80% of the time. It is the most important option to me on the car in my opinion. Every time I take someone driving in my car for the first time, the second I press the button people say "wow", it's that night and day.

Note: This is on PDK of course.

 

I have no idea, to take it a step further, the cars that don't move on the lot are the ones without SC+. It's almost as if they want you to custom order the car, since they make more money that way.