It depends the emulator that you want to use:
-
RetroArch CE offers 72 cores to try, shaders and other many configurations to try
- A few emulators could be better as standalone (e.g. ScummVM, FBANeo RL)
webMAN MOD lets to launch retro games directly from XMB.
Also you can create standalone ROMS packages using RetroXMB or webMAN Classics Maker.