I have it. Not sure how I feel about it yet. Seems to do well if you can line it up with incoming damage. Spreadsheet wise I think it's only second to the legendary trink depending upon the ilvl.
It seems pretty good actually.
Our HPala uses it to mitigate quite a lot of damage from several Nighthold mechanics and it seems to work nicely every time a group can stack to make an use for it i.e. Orb detonation on Krosus, Witness the Void on Star Augur.