So I am currently using the TB mirror trinket and heroic symbiotic worm. Was trying to decide if I should go after the mastery and on use strength trinket from tol barad. The impatence of youth should push all hits off the table. My guild is only 1/7 so I think more mitigation will be better.
Would you be equipping both mastery trinkets at the same time or are you looking to replace the Mirror?
Personally I would keep the symbiotic worm unless you have a real need to be block capped, the extra stamina is not useless and the procc is quite strong (if equipping the Impatience and using it will make you block capped, so will the Worm, and the Worm's cooldown is shorter than that of the Impatience).