Restoring an Ohneschwanzenegger nand will virginize everything except for potentially 2 things.
If bootmii installed as boot2, it will still be there after using ohneschwanzenegger.
Also, if u used Korean Kii to remove the Korean Key from a wii that was originally Korean, or to add it to a wii that was original not Korean, it will not restore it to its original state (since those changes are applied to the seeprom and not the nand)