Once you reach the cap of what CH can heal, you should really begin to focus on AC.
Most people here keep talking about how important HP is for tanks, but most parses shown on the SK boards I frequent have shown that AC is actually more of an important tool in the high end raiding content.
The AC and saves on this are VERY nice compared to what most ShadowKnights can obtain, but might be a little underbalanced for the difficulty of taking down Vulak.
All in all, I'd say a good Enchanter item... as they're always getting hit, but wouldn't be surprised to see a Bard interested in them just as much.