I don't think you understood the 64drive's virtual controller pak feature. It's not like the Nintendont GC one on Wii, or on various emulators. You still need a physical pak to save anything, the feature just lets you copy the contents to the sd card and back. Incidentally Everdrive64 has the same feature, with maybe slightly worse UI.
@Estil
N8 Pro NES should be out this month. There's various small improvements, sound, loading times and whatnot, but the only big feature is support for far bigger ROMs, like the Chinese FF7.