Originally Posted by
citizenpete
The more RPPM units you have, the more haste is required. With your gear I would go for: 2 Haste (gems) > Int > mastery > crit. I decided for me:
Long fights like Lei Shen: 2 Haste > Int
Multi Target (Council, Horridon or Animus - if its allowed to multi dot :P) 2 Haste > Int (IV not glyphed)
Short Fights like Jin Rokh: Int > Haste
But the difference isn´t that big (my personal experience), because of RPPM RNG. I think it´s time to gem Int somewhere around 50 - 55% haste, but as already explained, the difference isn´t that big (not worth the headache).
The real fun begins with 5.4, if Blizzard decide to not fix frost haste scaling.