I live in Texas (like you), but up in the panhandle...my brother goes to college down there in the dallas area (irving), he drives a black 97 Cobra with red rocker panel stripes, maybe you'll see him.
So, the emissions isn't a real problem.
Dynomax was my first choice, then I heard MAC and kinda liked them...and I heard good stuff about Magnaflow...then I heard a sound file of the Bassani Mufflers over at the Corral (not sure if it as the X AND the Mufflers, or just mufflers) and I liked what I heard.
Thanks for the sound file though, it helped a lot
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1998 Yellow GT 5-speed
Appearance Package
Black Hood/Fender stripe
17x8" Wheels
FMS 3.73's
Steeda Aluminum Pedal Covers