>>717561789
It's GUI works very well with a joystick,and then there's the shared shaders and not having to configure every emulator individually.

Also for CRT mangling shit it's pretty useful.
For example, my HDMI to composite adapter is a bitch that only do 1280x720 internally with a shitload of overscan, and being able to center the picture and use a pixel scale that is compatible with the device and all that trash is pretty useful, specially that it keeps the same settings across all emulators.