I have had the car now for over a month. I have tried TACC a couple of times and it seems to function decently. But it is not different from adaptive cruise on my Acura. I have tried to engage AP twice and on both occasions it has led to near disasters. Both were activated while I was in the middle lane of an interstate going at 65 mph. The first time it started to veer to the right and almost swiped a car in the right lane before I hastily took over the control of the car. The second time it started to accelerate to keep up with the speed limit of 70 ( had set 0 on my max limit). A gentle curve was coming up and instead of keeping up with the curve in the middle of my middle lane it started to cut across into the right lane. I had to steer hard to keep it in the middle lane or else I would have been run over by a 18 wheeler. The first episode occurred with the V9.15... and the second one was yesterday after a V10 update. I am now afraid of trying out autopilot any more. I mentioned the quirks of AP to the SC a week ago when I took in for rattle and their comment was that it was "beta". I have no other Tesla to compare to know if this is normal behavior or there is something wrong with my car. The SC is 100+ miles away. Should I ask mobile tech to check it and see if this is normal behavior of my car compared to other Teslas. I heard so many good things about AP and arriving refreshed but then mine wants me to not arrive at all and instead give me heart attacks.