Looks like the materials and finish, aside from the manufacturers being different. The Steeda one is chromolly steel vs steel, which would be stronger than just regular steel. It also mentions in the Steeda description that it's "on car adjustable" they both probably are though.
2011 Grabber Blue GT California Special, 3.73 Gears, 6-Speed Manual, Steeda CAI, Steeda 93 tune, aluminum driveshaft (The Driveshaft Shop Co.), MGW shifter, Roush axle-back exhaust, Roush Side Rocker Panel Splitters, Ford Racing BOSS 302 front splitter, sound-tube delete, painted plug covers, JLT oil separator. Shelby transmission scoop & powder-coated trunk brace & many more items...