Firepower!
One thing that was not touched on too much is that Colts are harder to get worked on now, and harder to get parts for. (if not now, then soon)
One of the two authors above mentioned that Colts go out of time easier than Rugers.
You should stick with your King Cobra unless/until you have problems. I suspect you won't. The only thing I don't like about them is that they're so damned shiny!