The Bottom Line: This skimpy pack is incredibly lightweight yet still manages to be an ideal mountaineering, ice climbing, and ski touring pack. If you have lightweight gear, this little number will serve you well.
This pack has been tested on rainy ultralight backpacking trips, scrambles, ice climbs, alpine climbs, mountaineering overnights, and ski touring in Rogers Pass, the Canadian Rockies, and the Pacific Coast Range. The longest it was worn consecutively was 14 hours. It has also been used for commuting with textbooks and laptops. The Trion even came along as my travel bag for a 10-day hiking trip along the Kumano Kodo in Japan.
I am always on the hunt for the perfect alpine pack. Sadly for me, I know what I want, but it has yet to be made. A roll-top pack with a removable brain, good helmet carry, removable hip belt, bivy pad for a back rest, good attachment for ice axes and ice tools, ski carry, and a pocket for avalanche gear all under 1 kilogram. Like I said.....dream pack. The Trion Light 38 manages to get the most important of these features together in a tight little package.
I'm a size medium or large in most packs, so this worked out well for me. The sizing is good, and I imagine it should work for people who find that medium or one-size-fits-all packs work. The frame bar, despite being one rigid bar, actually works pretty well and gives the flimsy pack a surprising amount of structure. It is not enough for loads exceeding then 12 kilograms, but it is plenty for anything less than that. But it moves well. I've never had a complaint climbing with it. It's just always comfy. Skiing with it was an adjustment from my form-fitting Quintic 28, but it's pretty darn good when everything is tightened nicely.
The features of this pack are numerous. There are two different ice axe attachments. The fastener tabs are mediocre, but I appreciate having loops and modern tool heads as options; this helps keeps longer mountaineering axes from sticking up quite as much. The front pocket takes my 265-centimeter probe and Evac 7 shovel a bit snugly, but well. My BCA snow saw sticks out a fair bit, but it's not he end of the world. It comes with straps for all three ski carry options. I also really like the fact that removing the "brain" turns it into a fully functional day pack. When you want to tuck away all but the essentials so nothing gets in the way of your harness, this is excellent.
The pack does feel kinda flimsy, though. This pack is not durable. The bottom is more burly, but overall it's a light material. I have ripped the interior pocket due to a crampon snag, though the outer material is still pretty good. To me this is mostly acceptable in the name of weight savings. The shoulder straps are really thin, though. Like 18-liter daypack thin. I definitely feel they could have added a bit more padding here because they have a habit of folding when loaded with extra weight, and the actual strap tightens and is very noticeable. The daisy chains on the front aren't great. I'm not sure why they are there because they lack the lower points to be useful for a crampon case or carrying a helmet.
Despite my pedantic preferences and shoulder straps that are on the thin side, I love this pack. I take it with me on most of my weekend trips. It's capable, and it can adapt to nearly every trip, no matter the season.