If you want to supercharge, definitely get a full exhaust. It will compliment every other mod and sound awesome. Also, look in to MAC, they are reasonably priced and solidly built with the largest collectors of any brand. You can buy them ceramic coated or in chrome (I sent my chrome ones away to get ceramic coated). I have the Mac longtubes and ProChamber (crossover) and the fit and finish are excellent. With no other mods they gave me a very healthy and strong gain from mid range to redline and they sound great.
Wrote a thread here about my exhaust only gains: http://mustangforums.com/forum/4-6l-...o-results.html
exhaust work with any forced induction is always a great way to build towards future proofing.
Mustang 5.0 mag did a header comparison and awarded MAC as the winenr fir their supercharged GT shoot out: