Ebola used to run a 5-man shadow priest gang on Magtheridon. Mind blast x5 was a one-shot on most anyone back before resilience. And enjoy your dungeon runs now while you still survive. When you hit 70ish, go try Shattered Halls or Mechanar/Arcatraz. There are bosses and 5-pulls in there that absolutely mutilate squishies. Which is pretty much why I stopped playing mine. :P

And let us know how far you get at-level. It's possible that the new talents or a particular build is viable for the normal mode stuff at level.