Just in case anyone asks,
I have the official 4.4.2 NC2 Kit Kat (100% stock and unrooted) and just installed the KNOX sub apk, and it is working perfectly. So far no issues. I am now a manager at my work and needed an extra level of security, plus I want to keep my work stuff separate from my personal stuff, Knox works perfectly.
It did not wipe anything or crash, but I recommend for anyone going to install this to do a full internal and external sdcard backup, you never know (knock on wood). Also if for some reason you get stuck in know and cannot get out no matter what (and cannot uninstall the knox app) as this happened on my wife's S4; reboot into safe mode. It will disable all non-system apps. This will let you backup your internal sdcard, just incase you need to do a factory reset.
- Turn off the device.
- Press and hold the Power/Lock key and volume key to turn the phone one.
- Once the device turns on, let of of the power button, but keep holding the volume down button
- Keep holding the Volume down key until the lock screen displays and says "Safe Mode" in the bottom left corner.
Reboot the phone and you should be able to be back to normal.