They're quite difficult to use without looking at them, and I've got better things to look at while driving. Better buttons that don't move and have "presence" than I can feel without looking.
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With touchscreens, it's not just that you lose the tactile component, but all these interfaces are modal, with buttons that disappear or move around depending on the screen you're on.
Oh, you're on the radio screen? There's no way to adjust seat heating from here... or if there is one, it's in a different place than on the AC screen.