The point was to keep it looking as much like a stock GT bumper as it could. The kickout at the bottom rear sticks out much more on the GT than the Cobra.
Besides, I have the GT bumper and not another Cobra bumper. If it can work right it might be an option for all those GT owners who want something different. Also the Gt bumpers are 3 piece, so easier to install and remove vs the one piece Cobra bumpers.
Aftermarket Cobra bumpers are usually held on with double sided tape on the sides (not the greatest). For my bumper I added (fibreglassed in) the factory side mount brackets to better secure it to the car. It was a bit trickier to install but it went on (not sure if it will come off someday easily though).