Normal guild kara run, 1 maybe 2 shamans - 2-2.5 hours
4 shaman kara run, every totem available - cleared to aran in just over an hour. Raid makeup: 1 Tank (warrior), 4 shaman (ele), Pali (holy), Druid (feral), Rogue, Warlock, Hunter

Didn't finish the run because it was late and the tank had to leave. All bosses dropped in no more than 1.5 minutes. Shamans just put out more dps and all around buffs than most classes as a whole. I was also able to off heal when needed. Mobs just died too fast most of the time, and the Pali just sat around and sometimes dps'd. I plan on trying my full team this week with 2 healers.