Haste and mastery at t12 4pc

[lyrics]

How much haste do u need at the t12 4peice and how much mastery is a good amount. i am currently refoging all mastery into crit or haste but i see some players reforge haste or crit to mastery. I am currently at 1900 haste unbuffed is that too much? i am also at 1150 mastery is that too low?

[Metaphoric]

You want about 1850 Haste with 4pc T12, all haste above that should be reforged to Crit, if Crit is already on the item, you reforge it to Mastery.