Commandos defiantly have the best survivability out of the 3 healers which will be key in 4v4's (assuming that people will focus target healers) being able to off tank, and put out almost 10k heals will be an interesting combo in arenas, In a situation where all 3 dps and tank target the healer, I see that commandos prevailing vs the other healers ( considering I drop ops/sorcs in a matter of seconds in dps spec )