Roman Rodyakin wrote a review of Backcountry Access Stash Alp55 Backpack - 3356cu in on January 12, 2010
This is my second year with this pack.
The pros have been covered by other reviewers below: it has an external shovel pocket, it has an external probe pocket, it has plenty of straps to attach skis, ice axe and/or poles to, it has an insulated hydration system, it has convenient hip pockets, you can access the main compartment from both the side and the top, there are plenty of straps to clip your gear to, great compression straps and IT IS LIGHT.
The only issue I have had with it so far was that the "Nalgene-compatible" hydration system on mine was not actually Nalgene compatible, so I replaced it with an MSR hydration system (that I still run through the insulated sleeve).
Other than that, this is a sweet light pack that works well for my purposes. I have used it for two- and three-day ski tours and glacier climbs in Washington Cascades. Nothing on it has ripped or fell apart yet. I haven't pounded on it with an ice tool, or jumped on it while wearing crampons, but I have bushwacked with it, glissaded with it, practiced prusiking out of crevasses with it and waded creeks with it. It has been rained on and snowed upon. It's still alive and kicking.
It would never occur to me to bring this pack on a rock climb (let alone to go crag climbing with it) -- this pack excels when you are carrying a shovel, a probe, an ice axe, a pair of crampons, a pair of skis, poles and three layers of clothing that you want to access from the side while having a few pairs of mittens, a facemask and other small things accessible from the top. If you are not carrying any of that, then there are many smaller packs of the same weight with probably a sturdier construction.
Finally, while I have occasionally loaded it with 50lbs or more worth of stuff (including a wet rope), I normally travel with less than that in my pack, even on three-day outings. Ultimately, the reason I bought this pack is that it's light, and so is the rest of my gear.