I don't think it's possible to reach diminishing returns on crit in this bracket.
I typically stack crit when there is a bonus involved (e.g. upon crit X happens or +50% crit dmg).
Sometimes I stack crit to get to a nice round number - like 20% or 25%. I'm not saying it makes sense...
But , at the risk of sounding like a broken record, get both and try them out. I am a big fan of multiple gear sets.
My opinion is use of the bandit but I am not well versed with hunters yet. I'm not sure if AP stacking is paramount.