Part of the safety of standard cruise control is the fact that it is clearly crude and dangerous - it keeps the driver engaged.
It was my first experience with lane departure warnings as well which was pretty neat but soon became a small distraction. I could see myself turning that off, if it was my daily driver.
The best feature of adaptive cruise control is how it keeps you a safe distance from the car in front (about 4 seconds) - whereas if I was using my own judgement, the spacing would probably be halved.