Howard Jones for Killswitch Engage was one of the most remarkable vocalists that was actually a hit. And also Jake Luhrs, even though he was with August Burns Red for basically their whole career. Same goes for Brian Fair of Shadows Fall, and Sam Carter of Architects.
Very true. Then you have the other side of things with Gary Cherone with Van Halen, Andrew Neufeld of CbK, Kristen May of Flyleaf, (You can make a case for) Brian Johnson of ACDC, Anyone other than Mark Chavez of Adema, Jason Moreno of Drowning Pool, and a few others.