I drove on my vacation this summer. It was cheaper, all I could afford, and allowed me to visit with three dear friends in the Northeast (New Jersey, Delaware, and Massachusetts). I've enjoyed XM radio since I had it installed about three years ago, but I appreciated it even more on this trip. I really didn't have to find new stations every 40 or 50 miles. Yes, no Rush or Bible thumpers.
I could listen to Air America and get even angrier about Bush, or I could listen to any of the presets that I made before I left, including all Sixties and all Seventies (to hear Steely Dan mostly) music stations.
Here is a tip if you have XM run through your FM radio: Remove the FM antenna. It reduces the chances of an FM station interfering with XM. I discovered this fact by accident when once at the car wash, no one reattached my antenna. I left if off for a few days and noticed a clearer XM signal. Now it stays off my car.