As I see it myself we are forced to use set pieces that got mastery(and maybe lower ilvl) on it instead of full dodge/parry gear that could be warforged if we are trying to go for a 4 set bonus.
So my question is, is it the extra rage realy worth it? (Heroic progress)
General consensus is no, the extra item level from warforged off pieces tends to out-perform the extra rage from 4 set, which (from what i gather) is a bit rng based.
Its not so much the extra item levels as the 4piece being utterly shit and given to us for 2 tiers in a row... Ontop of it having the worst possible itemization.
Get head/legs and go with dodge/parry off pieces