I look at OnStar as a backup plan.
My car breaks, I use my cell phone.
I have no reception or my batteries are dead, I push the Onstar button and tell them I'd like to sign up for a minimum period. My second call to them (30 secs. later) is to summon a tow truck. Always assuming that when I have no reception, OnStar does.....
Remove the box and you have one less option. I don't find that it bothers me - I usually have a GPS unit hung beside it when travelling anyway, so I'm used to not being able to see high up on the windscreen. Guess that means we'll see the saucers landing a fraction of a second after the convert owners will......