This is a question I have been researching lately. It appears that most any tire shop would have the proper equipment to work on runflat tires. In a jam the shop can call the tire company and they will Fax the proper runflat procedure to the tire shop. The problem arises when the shop has no employee trained to work on runflats.
My personal take on the situation is that many tire shops are afraid to work on runflats because they think they may scratch a wheel, ruin a sensor, or trash a tire. For what they pay the tire shop men I can see their point.
When time comes for my new tires I will go to the America's Tire shop where I know the manager owns and drives a C5.
Tom