I actually find sethekk (NORMAL MODE) to be the easiest instance to 5 box with 5 shamans. Here is a vid on me grinding sethekk, vid is only of killing Ikiss. I think I was around lvl 68 or 69 at the time of this recording =)

Note: You can probably tell I was lagging hardcore in the vid, fraps + crappy ISP + running wow all day took its toll hehe

http://www.youtube.com/watch?v=O6YEgc6qTXA