I had an E61 BMW 5, I think the nav/system/display was good. Now I drive the 4 series and the nav/system is not much different in terms of functionality, it's just a bit more pleasant on the eyes and higher resolution. Overall, it's the same story: I don't rely on it, and when I do use it it's an amusing reminder of in-car software, but it doesn't bother me. I've sat in the newest generation cars in BMW dealerships, and it seems like it's going to be the same story [ignoring things like CarPlay].