Manual or auto? What other mods? Consider the On3 kit instead of the Hellion as well. And look at the Vortech too if you supercharged.
What are your goals for the car? Are you going to be doing the work or a shop? You will obviously need a custom tune no matter what route you go.
2000 Mustang GT Steeda #0048
Just because I give you advice, doesn't mean I know more than you. Its just means I've done more stupid ****.