Re: XM radio and OnStar questions
Yes, you will have to pay for XM, once your free trial runs out. My free trial was 3 months. After that, you deal with XM directly.
[EDIT: OnStar uses Verizon Wireless, not satellite, for communications.]
As I understand it, OnStar and your cell phone are totally separate [unless you have Verizon for your cell phone and opt to link the accounts together]. You can use OnStar to make satellite phone calls, as long as you prebuy minutes from OnStar [though you can apparently opt to share your Verizon cell minutes with OnStar]. I think mine came with 30 OnStar phone minutes that expired in 2 or 3 months, but we never used them. The rest of OnStar (directions, etc.) was paid for 1 year for us with the car purchase. After that, you deal with OnStar to pay for the features you would like to continue, if any.
We just use our cell phones and handsfree bluetooth in the car. Just pair the cellphone and the car one time, and then from that point when you bring the phone into the car, they automatically make the connection. IIRC, the car can deal with 5 different cell phones this way. Then when the phone gets a call, the car quiets down (mutes the radio, turns down the heater blower) and announces the call, and then you can answer or ignore the call via the buttons on the steering wheel. You hear the call over the car's speakers, and can speak normally to talk. When the call is done, the radio and blower come back on.
OnStar phone is probably a good option if you travel where cell service isn't available. I could also see it being a good option for people that work out of their cars, assuming calls won't drop out as much as cell calls do (which I'm not sure about, since we haven't tried it). That depends on the service price too of course.
09 Silver Moss FWD 2LT w/leather, sunroof, trailering, & 8-passenger seating