Obviously both stats are the love of our life.
My concern is so many pieces of armor are one or the other. For example my current dilemma.
Wyrmrest Band
vs
Seized Beauty
That turns a solid case of Haste vs Crit almost equally.
32 Haste vs 38 Crit.
.85% Haste vs .98% crit
As it stands right now, I have 387 Haste, 625 Crit unbuffed ( with 559 unbuffed spirit which will factor with Molten Armor). I recently had BOTH rings on but replaced the Wyrmrest with Band of Channeled Magic and was thinking about buying another one soon to replace either of the aforementioned but again, it's a huge loss in crit with a major Haste gain and Spirit to give MP5 and some Molten Armor crit.