It's a gimmick.
Waste of time and money. While it's a nice conversation piece, that's all it is. Good thing someone somewhere was needing a kittykat upper, and silly him mentioned,
I am having a hard time finding a kittykat upper.
Ask yourself. What is the purpose of the build i am doing. Something for shits n giggles, or something practical. Myself, the 7.5 isn't practical. There is also the potential for cycling issues. Now you want to do a zippy 7.5" upper, do a 22lr set up. . The one i have rocks,.