If you're looking to step into heroics, the maw is a great choice for most fights. Personally, I dont use it on Morchok, Hagara, or Warmaster because after many MANY weeks of testing, I get more out of my 410 staff that what the proc offers on those fights. On all others, however, this weapon shines..particularly on Ultraxion and Spine...I even swap weapons in combat for madness heroic, as the staff is better during corruption phase and the mace is better when everyone stacks up!