For all you Dark Knights out there

I believe it was calculated that combining Power Guard's 40% and Achilles's 15% came around to a total of 50% damage reduction (physical). Keep in mind while Power Guard reduces only physical, Achilles reduces both magical and physical damage. But yeah, just a reminder, DrK's don't get Power Guard, so I mean the question is still Achilles or Healing? My observations are viewed as this:

Achilles - 30 SP - 15% Permanent Physical and Magical Reduction - Good for bossing, okay for training, more effective for larger damages
Healing - 25 SP - Heals 500hp every 4 Seconds - Okay for bossing, better for training, effective for smaller spread multiple damages (what I believe)