should i start stacking haste at 2-p or 4p set?

[Hotsumamage 0]

i know the guide said for arcane mages haste becomes better at tier 18, but should i start stacking haste soon as i get 2 pieces or wait till 4?

[Oltier 471]

i know the guide said for arcane mages haste becomes better at tier 18, but should i start stacking haste soon as i get 2 pieces or wait till 4?

Yes, as soon as you get 2pc

[Ghalt 1]

I have the 2pc, and I use Ask Mr. Robot for help with gear.

 

Should I just tweak the weights to be .76 for haste and .75 for mastery (simply switching the two values)...or is the difference in weight greater than that?

[JackuzeSilvermoon 0]

From my understanding you stack haste to 1350 or 15% before buffs are 2pc and haste becomes our best secondary stat ar 4pc. Slightly but still better with arcane missiles becoming our focus.