I never really rated either of the AC/DC singers. Bon Scott was good, but I'm more used to Brian. Neither should really be in this game though.
Never really cared for Anthrax, or Belladonna. I feel like his voice is way more recognizable since he came back to Anthrax though. On this song he's really not anything special.
And also, never really rated Coverdale either. Those old hard rock voices do nothing for me.
So Chris Cornell wipes the floor with the competition as he had the biggest range, best bands and most unique voice.