"Just on secondary roads not suitable for cruise. "
I would have thought the same, but on country roads and even in town, using the cruise control and setting the speed control at the speed limit or 5 mph above, the car pretty much drives itself in terms of acceleration, deceleration and stopping. You control turns .
Probably not as suitable for stop and go traffic as the acceleration is very gradual . But it works fine on country road with 40-55 mph speed limits, slowing when someone enters the road ahead of you, and bringing you to a stop at red lights when there is a car ahead of you.