Thinking about it over the years, if I had to do thing over, I would use faced. Face down touching the drywall below then 2nd layer facing up. Face paper is supposed to be a vapor barrier but with proper air seal and acrylic paint used now, how much moisture from below? With proper air management above, how much moisture from above and outside? My reasoning is that fiberglass insulation will be more efficient with less air moving through it with kraftpaper left on. At most, few cuts would let the moisture out?