Libram for Hyjal Trash

Hey guys. With the new patch, my guild has moved into Hyjal and bypassed KT for the time being. We went in and one-popped Rage last night and plan on doing him again today with Anetheron.

I tanked trash with no problem whatsoever using Libram of the Eternal Rest (+47 dmg from Conc) for additional threat. I'm wondering if it would be better to use Libram of Repentance (+42 BR) instead.

Thoughts? Has anyone done tests with this regarding damage taken vs. tps?
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Go for consecration one, or eventually in the future for Shahraz's libram


Holy Shield (and redoubt) get eaten so fast that the libram is basically useless.
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Thanks!
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