I've never driven a Tesla to compare, but the 2017 Audi A4 does lane keeping much better than I expected and would say the A4 is comparable based on what others have said about Tesla.

I think Mercedes has a pretty comparable system as well, but can't speak from my own driving experience.

It didn't include Audi, but FWIW the only head to head comparison I've read put Tesla far ahead of Mercedes, Infiniti and BMW - http://www.caranddriver.com/features/semi-autonomous-cars-co...

I'm still wondering what an automatic car(or merely one that has an automatic lane-keeping system) is going to do on a road like this:

http://gfx.dlastudenta.pl/photo_new/d90/b27/097/537/102764

Or like this:

http://img.sadistic.pl/pics/a87df587b218.jpg

Not everyone lives in countries with amazing road infrastructure, the pictures above were taken in a country that is a member of the EU,not some far Russian province.

Bring the car to a halt, and ask the user for help?

I've riden in a Tesla and I can assure you it does not anticipate or correctly react to all curves. For example, the 2016 Tesla S totally over reacted to this slight jog in 101, terrifying all of us, and forced the driver to take over. IMHO, not yet game changer.

https://www.google.com/maps/place/US-101,+Mountain+View,+CA+...