I had a flat 3 weeks ago. I tought that it was going to be difficult to repair because it was a run-flat. I waited 3-4 days before getting it repaired, and I drove probably around 300km on my flat. I just ensure to put air every morning. I had a nail in the middle of the tire so the air was not getting out quickly.
The repair shop laugh at me when I asked if it was going to be difficult to repair the run-flat. The guy there told me that as long as the puncture is in the middle of the tire, it was OK. He said that the only part that is different on a runflat is the side, which is reinforced.
So no big deal with run-flats. I must say that the first shop that I went too told me that I would have to replace the tire entirely... so make sure you shop around and that the shop you find knows what it talks about.