Well said, ccaats. Another major difference is that Bluetooth relies on a handheld phone using 1/2 watt of power. Unless you live in a major metro area, you'll be dropping calls all the time. The Onstar phone is a full 3 watt mobile phone with an external antenna and analog fallback. I know they said they pulled the analog plug this year, but there are still some rural areas where digital will just not be up to par for quite awhile. To me, it's the best of both worlds-Bluetooth so you can use cheap minutes and your contacts, and Onstar for all the things listed above!