Hi Trades,
Maybe you have sorted it out by now, but my experience with OnStar was very positive.
Visited a High School buddy and toured Delaware one day last year who had OnStar and loved it.
It is basically a combo of GPS and Cell phone, built in. I think they are always tracking you when the vehicle is running. For directions, you hit a button, a human comes on, you verbally identify your desired destination and they come back with route directions from your present location, turn by turn !!
No map display to follow, just clear, verbal instructions .... Turn left at next intersection with street/route number etc. ..
If you turn off the proper route they come on within about 25 or 50 feet telling you. You can respond that you are going to make a little "side trip" and you can then hit a button to signal them and ask to continue to your "original destination" from where you currently are and they follow up with instructions from that point onward, or give them a new destination.
If you stop moving and don't respond (accident) they send help. I don't know all of the details of how this works .........
If you lock your self out of the car and have a cell phone on you, you can call and they can "unlock" your car !!!! That took care of the $200 annual fee for that year !!!!!
That's my "personal experience thumbnail", I'm no expert on it !!!!!!!!!!!1
Take care,
Lee