I'm of the opinion that one should gear up around the drops one has, not around a drop that might not happen; I've lost count of how many monk mains I know who never got their helm from T6 throughout all of 2.2 and 2.3 and so got stuck eating bard food.

HQ Wootz Mask with those stats makes a very nice drop-in replacement for the HA Mask of Maiming, pulling ahead by 7 crit and 18 det while retaining the same accuracy. This is ~5 DPS better, and you could even add skill speed if you're feeling frisky. Heck, it's nicer than the i120 poetics helm if you can get the HP elsewhere.

With that in mind, what you ought to do with it is up to your own personal situation, like how hard your group (if you have one) is going after Coil, how much your gil is really worth to you, that sort of thing.