On my Pala tank Disc Priest and x3 Hunters I just unlocked visions on them - was 420 ilvl. I failed the first one, but then bought the orb upgrade, then managed to go straight to boss after first trash and get my cloak to 5 on all by repeating.

Trapping one of the guards was key for me.

Also I get reduced health in there by having one healer in the group. Upgraded to give the group more sanity as it stacks on all.