Control Room and ARC 2.5 or 3

When using ARC in the Control Room is it best to use a Pre or Post Insert?

Does ARC have anycomponents that react on a vertain treshold? Then,and in case you dont know if it might be better to use them prefader so controlroom volume doesnt affect this.

The answer is that I do not know so I will follow the pre fader advice - thank you.

No difference at all. Only really matters for dither. You don`t want t alter levels after applying dither (and no need to dither the control room).
For level dependent processing it depends on the desired effect. Both positions have there uses.