It is one of those scenarios where, you get what you pay for. The twin disc options have stock like pedal effort, while providing more than enough clamping force. Because there is 2x the friction material, the pressure plate spring doesn't have to be so heavy. Not only does this make for a better driving experience, but is easier on the hydraulics. Some of those single disc kits with very high torque ratings put excessive pressure on the slave cylinder and master cylinder because the springs are so damn stiff.Ok. I'll check into a twin Disc. Kinda leaning towards vengeance stage 2.
There's only one website you should trust when you are looking up part numbers. The manufacturer.
https://www.exedyusa.com/browse?search=2016 mustang gt
All of the parts sales sites get their data from the people that run the site uploading a spreadsheet of part info they get from their suppliers.