If you're really looking for an expedition quality bag, it needs to be Western Mountaineering, Valandre, or Feathered Friends. You're talking about staying alive through a storm on the mountain, and carrying the bag for potentially weeks over 10s of miles. Lightweight and warm as heck is the only way to go.
I added 2 sub 5lb -40 bags, but I did misread the bag you were referring to. The inferno is a great bag and would make a sweet drop if they can get it. My apologies. I'm surprised how many bags here are rated 0 or higher...