When i had the GC option it was cool. Was on the mild setting and sounded sweet, until...
It started misfiring, car would barely go and had to stop into a parking lot to just clear the codes and turn off the option...This happened a few times before i finally took the whole tune off my car thankfully.
Another bad experience was when leaving the track the GC *all by itself* went from the Mild setting to Aggressive... Made my car stall and when it didnt stall didnt seem drivable...
IMO i would not suggest this option to anyone just bc of my experience... but if it works fine for you op then