Systems with excessively complex interfaces of any kind in cars are bad. I drove a Sync-equipped Ford last year. The infotainment system and several functions directly related to vehicle control were operated with buttons on the steering wheel, but several things that were single-function in most older cars and aftermarket sound systems required looking at a screen or memorizing a sequence of several button presses.
Particularly bothersome, the option to disable traction control was buried four levels deep in a menu system.
I rent cars a lot when I have to travel, and I've grown to hate anything "touch" in a car. Several manufacturers have adopted touch-based controls, even outside of a touch screen. For example, I had a Toyota Avalon rental a couple of months ago, and I was constantly, accidentally pressing buttons because I brushed them with my hand. When a car is in motion, it's hard to steady your hand. With touch controls, I find that I have to plant a finger somewhere as an "anchor", then engage the touch inputs with another digit. What a horrible mode of interaction.
That was the second biggest reason I didn't pull the trigger on a Ford Fusion Energi a couple months ago (first one being Microsoft Software running critical car systems)
While Microsoft has a well-deserved reputation for making unstable and insecure consumer software, think about any software you've used made by companies whose primary business was not software and ask yourself if Ford would have likely done a better job in-house.
Particularly bothersome, the option to disable traction control was buried four levels deep in a menu system.