This evening I did a 185 mile drive and 175 miles of that was M'way using Adaptive cruise
Have cars with cruise but the first time with adaptive, two small anomalies noticed
1) When you are in the middle lane doing 73mph, ahead of you in the nearside lane is a coach, you come to a right bend so that the bus is in your line-of-sight...cruise thinks it's in front of you and slows you unnecessarily.
2) Your in the inside lane doing 65 but cruise is set to 73 but the car in front of you leaves the M'way, the car tries to accelerate as quickly as possible back up to 73. Now the driver in the middle lane doing 70 who thinks he's about to pass you thinks you want to race as you've increased speed.
That said the system is quite intelligent as pulling out from the 1st lane to pass something in good time, a driver from the overtaking lane pulls in in front of you. Although he is technically closer than the car in the 1st lane the system seems to know that his speed is higher and the engine doesn't brake.
Oh, are your rear brakes applied when cruise slows you?