I got my S85 about two weeks ago and have been having a ton of fun with it. One of my amusements has been watching the car skillfully handle heavy traffic using the TACC feature. It's a little more aggressive than I'd like (even set to 7) but it's a wonderful feature that makes dealing with traffic (a near-constant reality here in the DC area) so much nicer. I'm a computer programmer and I like to understand how stuff like this works, so naturally I've started wondering just what kind of data the radar sensor provides to the system. For example, is it able to scan from side to side? It seems to understand turns to an extent, and stays locked on to the car in front of me even though it's a bit off to the side, rather than switching to the concrete barrier directly in front and bringing me to a rapid halt. Does it provide doppler info, or is it just providing distance measurements? What kind of range does it have? One thing I'm particularly interested in from a practical point of view is, how fast can I be going and still have the system safely bring me to a stop before hitting a stopped car in my lane? Does it work all the way up to the top speed of the car, or is there some lower limit imposed by the radar's range? If anyone has any info about this, or pointers to where I might find it, I would love to know.