When I say "two" to begin dialing a phone number, the pleasant- sounding voice typically responds "pound" (for the pound symbol on the telephone), and the call can't be completed. Even with the top up, you have to lean directly into the speaker--an unnatural pose while driving. Once I locked my keys in the car but remembered that OnStar customers can have their cars unlocked remotely by calling a toll-free number. I called but was told, "Sorry, it doesn't work for your model."
Just to feel secure, I always keep a cell phone and Automobile Club card handy. One feature I like: In an emergency, press the red OnStar button, and the service can quickly contact the police. I haven't used it yet, but it seems like a good defense against road rage--another modern-day trend.