I have a November 2020 Model Y Performance (SW: 2021.24.11) and while I love the car and have zero regrets about buying it, I've taken it on 4 1000+ mile road trips so far and on my car, the auto pilot needs improvement. My issues are the same as others have posted:
- Phantom braking. Usually happens when passing a tractor trailer. The car will brake extremely hard due to the slightest movement of the big rig. Far too cautious IMHO. Phantom braking also happens when negotiating some curves. It seems like taking a tight curve at high speeds is the most common trigger in this scenario. Finally, sometimes the car phantom brakes on a clear day (daytime, not night) with no other vehicles in front or beside me.
- Very slow to resume the set speed after it slows down for traffic. This is most noticeable when coming up behind slow traffic in the right lane, I move to the left and it takes too long to resume my set speed (again IMHO).
- The default behavior of trying to keep the car centered in what it thinks is the lane leads to some jerky driving. This is most evident when in the right lane and you pass an on-ramp. Due to the lane marking to the right disappearing for a bit, the car thinks the lane has suddenly widened and centers itself. Then when the lane resumes it's regular marking on the right, it's almost always a hard jerk to re-center.
- In stop and go traffic, the car brakes late and hard. I've had to force myself to trust it and in general I do now but it's still very harsh in stop and go traffic.
Despite the above issues, I continue to use AP and just live with the annoyances since overall, it does make long interstate droning less tiresome. Still, I personally feel Tesla needs to make some serious improvements to the Auto Pilot AI if their "Full Self Driving" has any chance of being useful.
The biggest improvement needs to come in the AI's ability to anticipate traffic. As a human, I've learned to not only "read" the vehicle directly in front of me, but also the vehicles 2-3 ahead of that one to anticipate what traffic's going to do. Auto-Pilot obviously only reads the vehicle immediately in front. I will still never completely trust auto pilot but I will continue to use it to make long trips less tiresome but with my hands on the wheel and scanning the road constantly.