Matt,
This is not a proven answer to your question about why more Superformance Cobras are for sale than any other brand, but I would speculate based on the ones I have seen and ridden in that since they have sold so many more than any other brand, some of the owners are moving up to Kirkhams and such. I think it is more of there are just more of them to be sold than any other brand than anything to do with the cars as they are great.
Ron
