Folks in this thread are getting confused on the terminology.
Radar guided cruise is standard with tech package. Regular radar cruise will cut out under 20 mph or so and you have to re-engage when you get back up to speed.
Radar cruise with Stop and go means the cruise will bring you to a full stop, then pick back up and keep you moving as traffic moves. HUGE advantage when you are in bumper to bumper traffic.
Adaptive cruise may be how Ford is marketing the radar cruise with stop and go. I am not sure about this one.
So... 2017 owners need to chill out. None of us have what I am asking about. Hence the question about retrofitting.