Look at the design of the Borla....the same loop as the stock obstracting direct airflow for more HP gain. Now, with my magnaflow..I'm very happy with it as of now until some company will come out with a better exhaust ( not just mufflers like Magnaflow and Borla ). I was feeling good about Billy Boat's exhaust set-up with the Crossfire Speedster but was disappointed that they're not willing to manufacture one for the crossfires.