I looked at all the alpine packs for what I do. Ice Sac, Nozone, Cold Cold World, Alpine Attacks, Marmot, Black Diamond. I do not ski or snowboard and I wanted something light. I knew that going light would mean lighter loads so I was looking in the 4000 cubic inch area. The best pack I found is the Climb High Jackpot. They only make limited ones becuase Climb High's supplier doesn't make enough. It works well for weights under 30 lbs. I would not trust it for weights over 30 lbs because it does not have any type of frame--it uses the foam pad for support. I am not an expert on cloth types but it feels like that spectra cloth used on the Kelty's.
The Climb High Jackpot has tool tubes, crampon pouch, removable top lid, side compression straps that have buckles (a must on any alpine pack), removable bivy foam pad, inside pouch to hold water bladder, and extendable main compartment that goes to my hips if I need to bivy.