Not sure about the price (it was a Christmas gift from my Dad)...but I have true dual exhaust and Flowmaster 44's and I'm really satisfied with the sound, although I MIGHT get some hi-flow cats to replace the stock ones. I too have the 4.6
Maybe someone could post about the price, but that's my set up.
1995 Thunderbird LX 4.6 (stock for now!): Xenon Kit, Air Silencer removed, True Duals with Flowmaster 44's - GONE BUT NOT FORGOTTEN - I will be back one day with another MN12