I truely don't see how you can go wrong with 1 of the big 4 out there. FRPP(Ford Racing Performance Parts), Roush, Steeda or Saleen. They ALL race what they sell!!!!!
Vortgland is good also. About 1.2" drop + a nice ride as well. Was told they make them for Steeda and a few others as well. Can be had for under $200 shipped.