There's a place for harsh vocals, I think. It's just when they're used exclusively that they make something seem, if not difficult to listen to, than just boring.
Thanks for sharing. That Wintesun clip has a ton of energy; I like it. And it looks like that guy can actually sing.
Well I'm glad you like that one. Jari, Wintersun's frontman, is considered to be a modern Mozart. Check out their other two clips from that live rehearsal if you enjoyed this.
I like when there's a mix of clean and harsh vocals so it don't become monotone, just like you said.