Simply following directions isn't a problem, it's when you need to revise the route etc. that problems can occur. I'm sure the manual says you mustn't do this when on the move, but human nature being what it is ...
A TomTom or equivalent is still a distraction, but at least it's up on the screen in the driver's eyeline (which of course is why it's not an elegant installation like COMAND!). Data input also seems quicker and easier with the touch screen, although I use the wireless remote for mine
which is mounted in a holder on the dash, right next to the steering wheel. The remote is very simple and can be used with one finger without looking at it at all.