The Ozzman
Melted by feels
Avenged Sevenfold rule
I wouldn't go that far, but their music is not as bad as people claim it to be. Like I've stated before, the first album doesn't sound like anything they did after it and it's one of their best albums.
Also, when was he in Black Sabbath? I'm not sure that's true but if he was it was probably a replacement for some tour dates or something.