How big is the box of this game? Is it another 'giant' of a box like the first Descent or the DnD Strategy game in the same genre? Or more compact?

It's smaller than the original "coffin" size box for D1 or Horus Heresy. AoC uses the (then) standard large size box like Middle-Earth Quest, War of the Ring (Runewars too I think).

Thanks!