I just got this car a few weeks ago and the unfortunate reality is that if you take your hands off the wheel after about 30 seconds you get frantic beeps and flashing warnings that give you about 10 seconds to take control back before everything shuts off and you're on your own. So the moment you potentially need your car to drive itself the most (say heart attack or something) it just says 'NOPE!' and lets you drive off the road. I'm guessing the emergency braking will at least still work.

That being said it's still pretty awesome propping your hand on the wheel and letting it drive itself when driving down a boring interstate.