In 1998 MC would be the superior for sure. But in 2012, NO MA'AM! Monica would slay her. Monica's voice is very powerful. I realize now that she often holds back. The only reason Brandy keeps up during their duets is because she knows how to adlib and she brings emotion to the song. In terms of actual power, I would place monica in the same room as J-hud and Xtina.