You shouldn't be comparing the Shelby to a stock factory offering. You should compare the Shelby to one of the Challengers from Petty, Mr. Norm or Saleen. That would be more of an apples to apples comparison and those cars will run/out run the Shelby.
I do have to say that Shelby is one hot looking car.
BTW, the Shelby starts at $50K and a SRT8 at $43K. That $7k will get you a supercharge kit and over 600HP.