Take a look at this video review of the Model X: http://youtu.be/jtQZ7WK_S8Y
You will notice on the AP display that it will continue to track a car that's turning left until the tracked car is far into the turn. The vision of the Model X radar appears to be wider than that of the Model S. I have never seen my AP display track a car that far obliquely to the side. Anyone aware if the AP hardware is better on the X? It could also be a newer Mobileye camera with a wider focus, but I believe it's the radar doing the vehicle tracking at that distance.