Tier 8 4pc bonus

[Squashed]

I just got my 4th piece of tier 8/8.5 loot last night. Currently am rocking the 8.5 chest & gloves, 8 helm & legs. For the headpiece I also have a superior item in the Ironbark Faceguard. I'm at a dilemma as to what should be my most used set, 3 piece w/ironbark or 4 piece w/out. I'd lose some expertise in the 4pc set, but having the availability of the CD seems to be a pretty big bonus. Plus, I'd get more used to using it a a magic reduction CD insted of a blocking CD.

I think in my Ulduar fights there is some burst magic damage than I can mitigate. The two biggest hitters are probably Hodir, Mimiron & portions of the IC fight.

Any thoughts on where/when to apply what sets?

[Hamburglar]

Situations I would use 4pc for tanking in Ulduar:

-Hodir
-Mimiron
-Steelbreaker
-Possibly add tanking on Freya to mitigate detonating lasher explosions or lasher nature attacks