So what would be the 2 BiS for both classes?
sin tank: and of the elite war hero +120 mitigation stats. the absorb proc when at 1600 mitigation pool gives 0.3536 squishiness whereas 1700 gives 0.3522, so +100 is better than +455 of absorb for 6/20 of the time. i have already shown why the healing one is bad.
ive never played a merc spec, but typically, the dmg proc relics are best for classes which has a large amount of dots in order to ensure the proc has as much uptime as possible. i know for lethality and madness/hybrid using the PvP vs. the proc is a 10 dps difference about. the on use power has been shown to have a time average power superior to the PvP ones, but I have not seen conclusive sim data for mercs in regard to dmg proc vs. power pvp.