I've tried out the Alpha gyro, which is exactly like the DBox, and it extremely limits drift angle. It also requires countersteer. Without the DBox/Alpha, minimal countersteer is needed since you control angle and drift recovery by throttle manipulation.

The only ways I can see it being used are ONE: at RC drift expo where HPI wouldn't want people to destroy their demo cars, and TWO: at a sanctioned spec class drift event where everone must run the driving aid.