mac or flowmaster with bassani x pipe?

[horse with no name]

Hello fellow mustangers!! I am ready to upgrade the exhaust on my 88 GT. I am looking to go with the american thunder kit from flowmaster with a Bassani x Pipe or a mac h pipe and after cat. I have read a couple mags, and in one test the h-pipe actually flowed better than the x, however it was not the mac piece. I am also concerned with how the x pipe will fit into the hangers and with the flowmasters..Anyone have either combination?? Thanks in advance!
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88' Gt//World Class t-5z tranny, king cobra clutch kit, hurst billet plus shifter, edelbrock timing chain,optima gell cell battery, 9mm motorsports wires, maximum motorsport brake upgrade kit w/ stainless steal lines and caliper sleeves, ect.. Power slot rotors, 16" boyd rims wrapped in bfg, g-force rubber