First, I don't like Autosteer (autopilot), as I think it is a little too sloppy because highway lane paintings are not very good in some places. It does much better when tracking a vehicle in front, but I prefer to be in control because it gets a little scary for me personally when I'm traveling 1 foot away from adjacent vehicles and going around a curve and expecting the car to steer for me... This is mostly a personal thing for me - I prefer to be in control of my own fate... you might feel differently.
That being said, I love the Traffic Aware Cruise Control (TACC) - it's light years ahead of any other manufacturer, as it uses the Tesla computer vision system.
What it does that is really amazing is that you can set the speed to +10 (which is what I do) and with one flick of the steering wheel paddle once you get on the freeway it will set your maximum speed to 75mph (in a 65mph zone; +10) and it uses the computer vision system to determine when it needs to slow you down due to a vehicle or obstacle in front of you.
The amazing thing is that because it uses a computer vision system, it is smart enough to not brake when a vehicle is directly in front of you but you are going around a curve so you will never actually hit the vehicle. In other words, it keeps your maximum speed, with safe following distance, no matter what type of strange curve or oncoming traffic might normally fool it into emergency braking.