I've only had the beta for a few days, but so far I'm surprised at how badly it drives. I knew coming into it that it was nowhere near ready for real world use, and that I would have to monitor its actions vigilantly. But in the dozen or so times that I have engaged it, I've never gone more than about 3 minutes before being forced to disengage for some safety reason. In one case it screamed at me to take control - for no obvious reason - no more than 5 seconds after it was enabled. In general, it accelerates much too quickly and waits far too long to apply the brakes. And that's in "Chill" mode.
I've read a lot of comments suggesting that it relies too much on map data (which may be invalid) rather than what it sees with its own "eyes". But there are times when the opposite is also true. On one road that I drove several times over the weekend, there is a stop sign that appears quite suddenly and close just as the car comes over the crest of a hill. Each time, it has to jam on the brakes to stop in time. I can think of at least 3 ways it could avoid that: 1) Reading the map and realizing that there was a major crossroad just ahead, 2) Taking note of the "Stop sign ahead" warning sign as it is climbing the hill toward the crest, or 3) Learning from the last time it crested the same hill. It is apparent that it does none of these.
This is just one example, but there are innumerable others.
I've read a lot of comments suggesting that it relies too much on map data (which may be invalid) rather than what it sees with its own "eyes". But there are times when the opposite is also true. On one road that I drove several times over the weekend, there is a stop sign that appears quite suddenly and close just as the car comes over the crest of a hill. Each time, it has to jam on the brakes to stop in time. I can think of at least 3 ways it could avoid that: 1) Reading the map and realizing that there was a major crossroad just ahead, 2) Taking note of the "Stop sign ahead" warning sign as it is climbing the hill toward the crest, or 3) Learning from the last time it crested the same hill. It is apparent that it does none of these.
This is just one example, but there are innumerable others.