He did some interesting stuff in all the years he was active. Ronnie Dio and the Prophets was good old time rock and roll. On Roger Glover's The Butterfly Ball and the Grasshopper's Feast he did some truly beautiful vocals. Elf was a fun hard rock band initially using a piano instead of lead guitar. Then he did a little bit of gospel with Kerry Livgren of Kansas on Seeds of Change. He could carry a tune in his younger days and had an awesome growl also. The last live concert he did with Heaven and Hell was decent, although you could see he was struggling to belt out the vocals. In interviews he always sounded like a very down to earth person, totally opposite to his "evil" stage persona.