I've done all the new dungeons, but yesterday was my first time tanking it. We made it through, though I felt a bit squishy. Luckily a few tank items dropped which probably helped my healer.
I've been really unlucky in the previous 2 dungeons. Most of my gear is still Poetics, with many of the items upgraded. I think I started with DV earrings and maybe a ring.
Either way, this is making me swear off roulettes on my tank and just run with the highest level dungeon. I might go back and do Level 50 roulettes on PLD and WAR to get the last bit of Law I need to upgrade.