Brand X being a representation of the subjects (Mustangs) Competitors. (Other pony Cars, Camaro's, FireBirds and...well thats about it) Its a polite ways to point fingers in a general direction.
Its true about alot of it wieghing in on the Drivers ability, I've seen guys who can make Cobra's and SS loose to a 100 percent stock V-Tech (Well not really

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64 1/2 "D" code Red Mustang Coupe. 289, C4, Mallory duel point. Ported & Polished 65 heads shaved .01 with 351 valves, 11:1 comp, 1.7:1 rockers, blue wolverine lumpy cam, modified 4100 Hipo 4 barrel. GT Apperance pkg. And to many others to list
2000 Perf Red Mustang GT. 5spd. BBK Underdrive pulleys, Flotech off-road H pipe. Hurst T-Handle, 40 series Flowmasters, Steeda Tri-Ax
64 1/2 red 6cyl coupe. Future resto.