The very recently observed production ratio 3:1 between Sc2O@C-78(C-2v/3) and Sc2O@C-78(D-3h/5) endohedrals can be reproduced in quantum-chemical calculations though only after a transition from the DFT to MP2 approach. It is concluded that the C-2v/3-cage-based species should be lower in the potential energy by about 1.5 kcal/mol.