I'm swapping, so I'm no longer a potential customer, however here is something to compare to (OBX EL):
My 1999 (MAF) RS had intake, catback and was catless. This is fairly low reading mustangs dyno (GST Motorsports).
If your header can produce power like that, it's definitely going to be a good header. But do note that the OBX header can be had for about $300 shipped. So if your design is truly superior, I think it would have to produce the best dyno results of any NA header out there. Can't wait to see the finished project!