I voted for the 5 class option.

I really enjoy my warrior, priest, mageX2 and warlock group. Shackle, Sheep, Seduce and Banish makes almost every mob grouping simple. I do have some problems with some of the bosses scripted events, but thats just a matter of learning the timing and strats. An example would be Capacitus in Mechanar, trying to avoid the bombs while watching his colors is very trying. I'm still working on gearing up and learning the zones. My ultimate goal is to be able to do heroics "solo".

Thats just for PVE. For PVP I've contemplated working up 4 warlocks and a priest. Its a tough decision, warlocks or mages?

Start over? Bleh...