brake controller

I've a time-delay type on the Jeep and a P2 on the new TV, a BMW X5. The main difference I see is in the jerkiness factor, especially when at/near a stop. It also makes a big difference on a gravel road, when there is a tendency for the trailer to lock up and skid with the former, but not the latter. The time-delay type is impossible to feather off to a gentle stop, it always jerks to a halt, and it releases with a jerk when you go to take off with a green light. With the P2, you wouldn't know the trailer was back there unless you looked in the center rear-view and saw only blank whiteness.