[Renzokuken]

PvP gear isn't fine for tanking. Zero avoidance and defense, and the sockets won't make up for that. Better off getting real tanking gear and making up the stamina you'd get from PvP gear with sockets (As everyone should).

EDIT: Albeit, there is a bit of leeway. You can use a piece of PvP gear for tanking if you just can't get what you want to drop (Usually people opt for shoulders for epeen, but they look like **** anyway so i don't know why they bother). But if you start stacking on more than one PvP piece you're gimping yourself and whatever group/raid you're in.