I rented a Nissan that would scream at you for deviating from a lane. I couldn't turn it off fast enough. Driving on a small winding road was constant false positives. Even on the highways, faded and repainted lines was throwing false positives. It was more of a distraction than a help. When driving in an unfamiliar city I didn't need the car distracting me with its disfunction.
Turning it off was buried deep in a menu that was not convenient to find. There would be no way to quickly or safely toggle it on and off as conditions vary.