Callas is far, far more, sometimes overly, theatrical than Sutherland, and overuse her chest note even in singing bel canto operas like Norma and Lucia, which is a big no-no to my taste. In general I prefer singings of the style that let the music speak it all, unfortunately Callas doesn't quite sing this way, she tends to put herself between the music and the audience. That can be okay for Verdi operas and alike, but in bel canto operas, it's the superb vocal quality and the superb technique that deliver such quality that wins, and singers must not stand in the way. That was probably why Callas told Sutherland she would never sing Lucia again in England when she and Schwarzkopf listened Sutherland's Lucia dressed rehearsal in Covent Garden in 1959. She never did sing Lucia again in England.

Callas and Sutherland are both great dramatic coloratura sopranos but they are in different ball parks.