is better use individual emulator example snes9x, zsnes, higan or retroarch?
only you can answer that. I, for one, don’t emulate outside of RetroArch/libretro.
What does “better” mean?
best emulates, best image, best sound, best brightness contrast and color
The cores are the same emulators.
Ok, I understand.
No, In many cases RetroArch is better than a standalone emulator, RetroArch has an advanced graphic api and perfect synchronization.
Some examples tested by me.
MAME is faster in RetroArch, try using a shader in satandalone or disable frameskip in demanding 3D games and you will notice.
On 16 bit consoles, RetroArch has less input lag than many standalone, 1 frame or even 2. And the resource consumption, is lower on RetroArch.
In Genesis GX plus, you have a huge variety of audio chips that you don’t have in any standalone.
In addition to this you have some exclusive enhancements, such as cores that have widescreen capability., or shaders that are able to change the color palette of a game or shader that change the meshes by transparencies or colors.