I have a 2018 cx5 I have read the manual and spoke with the dealer no one can tell me the difference between FAR-MEDIUM-NEAR settings what happens if you pick one on these settings over the other

 

These setting determine how far ahead of the car the sensors look when determining whether to brake or change the speed. Far looks the farthest ahead, but is more prone to slowing down the car when it is not needed, though it is the better mode if you tend to drive fast.

 

What schmieg said is correct, its basically the sensitivity or freeplay of the systems engaging.