its going to hurt with priests your fear and silence are very short range. You would be much better off with 4 locks and 1 shadow priest. at least with them you have more dots, pet bubble S/L 4 locks and shadow weaving are nice. my 5 v 5 are now very well greared with 300 plus resiliance. they also have very effective ways to deal with fear. Locks have 2 fears they can also heal themselves (if speced right) I still do not think at grp of all cloth can do well on 5vs5. Wars and rogues have to many ways get close and stay close.

3 mages and 2 holy priests may work out. hands down best 5 man is 5 orc shammy. my pve grp is 1 prot war 1 holy preist and 3 arc/fire mages. Ihave pvped with this grp . you have to have 5 pcs 5 screens and 5 ways to have a new leader and follow assist set up. once they know what your main is , they go for it.

I do pvp with 1 shadow priest and 4 afflic locks fun in bgs and world pvp. but in 5 vs 5 they have little chance to with against many teams that have full season 2 and 3 gear. let alone the raiding teams at put up 5 mans.