Cissy, If you like the Borla on your Miata, I think you'll love it on your Crossfire. One of the Techs at the Dealership where I purchased my Crossfire has the Borla on his Black Base Crossfire Coupe. He also has K&N filters. IMO it sounds GREAT! A much lower tone and not too loud.
I see the Borla in my future too (after my second Daughter graduates from college).