I had adaptive cruise control and lane keep assistant in an E Class (W213). Worked very well and these are great safety-enhancing systems, but I have to admit, I switched off after some time. Not because the systems were bad, but simply they did not add too much value. So for me, I do not require them in a new car. I would also say that it depends a lot on how they work. I tried the adaptive cruise control in a Toyota and did not like it at all. By far not as smooth than in the E Class. I know these are different classes. But clearly,- an adaptive cruise control systems like the one I tried in a Toyota, I would never use. For me, suspension comfort and quietness in the car and fuel economy are much more important.