I'd probably not recommend ACC on a twisty B road though.... it of course will either run at the speed that you set or the lower speed of the car in front.... some bends can be "interesting" when it ploughs straight through them on ACC, even if the speed is not too much for the bend, the way it enters the bend on the throttle can be alarming!
On motorways and dual carriageways and decent A roads, I have it on maybe most of the time.
With DSG it will be even better because it will go all the way down to a stop and then start off again... on manual, it won't - you get a "apply brakes" message and have to intervene, but that's ok for me for now.