The “audio alert” given by the program proves to be very punctual when travelling in town or small villages, as the alerts are given with sufficient anticipation.
Instead I believe the alerting system become less effective on highways or expressways, where the speed of the vehicle is much higher and the driver’s reaction to further maneuvers is evidently reduced. There is in fact no “preliminary” alert of the subsequent step to be taken, such as “You exit will be at 1000 meters”; this preliminary alert would give, in my opinion, a sort of range of the “distance” for the future moves the driver would be shortly taking. Instead the direction or exit is announced with such a minimal anticipation which put at risk the correct direction to be taken, as the driver might not be reacting timely, or might be forced to hard braking and eventually even miss the path.