For real, these lipsticks and mascaras can rip your team up in seconds. Sry, couldn't resist.
Keep in mind that you might come in situations, in which your spriest should burn mana instead of nuking, e.g. turtle teams with two healers. IF those teams survive your first burst cds you'll have a problem, because they last longer and you and especially your priest won't win a manafight - so burning mana would be much more efficient.