many ppl tried to compare Cala vs Manticore
even my self been switch from manticore to Cala due to the fun using it.
on manticore, we bounded by attack speed, so we focus on high dps skill or spell,
but in MP8 or higher, hatred and discipline running out due to long fight.
but on calamity, due to it attack speed, most of the time we not facing hatred and discipline problem,
so long fight not a issue,
with aps >2.8, we can perma stun and perma gloom.
other than resource issues,
we can have different build on Calamity.
Bola or Grenade? both doing well.
all based on my personal experience.

Just to add, the other reason of high disc regen of cammy is, 10% cc bonus from using 1-H bow.
i.e. if you have 51% cc with Manti. You will get 61% cc with cammy.