Comfort/Adjustability
Designed for use over layered jackets, the Trion’s padding may feel stiff to those using it in not-so-wintery conditions. That said, its combination of a robust frame and full-coverage hip-belt made it considerably more comfortable under heavy loads than most light-duty daypacks of similar capacity.

Weight
Especially considering its alpine predilections, I felt that the Trion Guide’s stated weight was a bit hefty for its performance. To be fair, this is “packaged weight” that includes both fixed and removable accessories, and I was able to cut significant ounces on most trips by leaving superfluous pieces at home.

Capacity
The Trion Guide is not a daypack in this category. It is fully capable of managing compact multi-day loads when expanded, and didn’t even flinch when I crammed it with nearly 40 pounds of necessary junk for a three-day Sierra climbing trip. Next time I’ll bring the tent as well since I am confident that this Mammut load-monster won’t mind.

Organization/Access
While this pack sports some nice organizational luxuries—zippered panel access as well as a large and useful front crampon pocket—I would have traded either for a light-colored interior. Extra access points don’t help much when the inside of your bag is a black hole.

Features
The Trion Guide bristles with functional extras, ready to easily carry skis, rope, ice tools, crampons, and other gear. Even better, some of these little conveniences are simple to remove if they’re unnecessary for a specific objective. My one gripe here was with the unfortunately fixed Velcro axe-keepers: Replaceable shock-cord loops would have been much nicer.

Value
The high asking price of the Mammut Trion Guide 35+7 was balanced by high marks for durability, versatility, and overall awesomeness. Though it seems a bit expensive, it packs enough performance to make it a solid value for those carrying heavy metal in the mountains.