I've had good success with my boosted monks (1 blood dk and 4 mist monks.. they put out good dps even in heal spec). The time things fall apart is usually due to mechanics like last boss of brewery when you have to get into the bubbles quickly (usually end up loosing a few guys) but can still kill him after a while. The heroics gear is lower level than what you get with boosts so technically you outgear it anyway.