I really like this pack and have taken it on Elbrus, Vinson, and Denali as well as other trips. This bag is waterproof (almost) and can carry more than you can and comfortably. It is also extremely durable and can handle crampons and axes being thrown around with it easily.
My only gripe is that on all of these bags that I have seen, the plastic piece that's supposed to give you head room has broken off. It is ridiculously flimsy and that's why I didn't give 5 stars.
The photo is me on the 16 ridge of Denali's west buttress doing a double carry. Pack was STUFFED! with about 95 lbs.