I had a loaner for a week (S 100D). One of the first things I noticed different from mine was the ease in which the auto steering disengages when making a lane change on non highway roads. In fact as soon as I would put the blinker on, it would disengage. The lane change is very smooth then I can reengage auto steer. With my X I really have to apply some force in order for the auto steer to disengage. To a point where the car swerves. I prefer to only disengaging the auto steer and not both steer and TACC to maintain speed. I few days in to the loaner experience, I noticed the auto lane change was not working on highways. I concluded it must have been turned off. So, I went to settings and turn it on. All of a sudden, the brute force auto steer disengagement was back. When I received my X back yesterday, I confirmed that with auto lane change off allows a smooth disengagement with very minimal force for non highway roads. I now prefer the setting to be off primarily. I will probably only turn it on when on extended highway drives. The S100D was AP 2.5. My X is AP 2.0. Saw the same behavior on both platforms.