I'm used to trekking with military gear, lots of pockets and places to latch stuff to, enabling one to carry way too much gear. This pack is good for downsizing to the essential gear as it will force you to minimize given the few external pockets. If you're looking for light, this pack definitely is light and with proper adjustment (see notes on the buckles below) you can make it fit very comfortably. I have two buds that love this pack as is and have been trekking with it for over 4 years now so it seems to hold up well.
Nice layout but it's really like a 70L pack in size, very narrow and long and tall. I'm guessing the other 20L are when you extend the top another foot above your head (which this pack does).
Zippers and fabric seem tough enough to last quite a while.
It snugs down well, so with a light load you can really compress this pack.
It's narrow so it's easy to squeeze through tight areas (crevasses, bush, etc.)
Water bladder pocket is huge.
Middle front pouch is great for putting stuff you need to get to quickly: rain gear, gloves, cap, etc and it zippers open into the main pack area.
The plastic buckles are very cheap plastic and don't latch when pulled snug.
The hip belt is very, very wide and feels odd and oesn't have places to connect stuff to it.
The D-rings on the shoulder straps are too high up, they need to be 4 inches lower or adjustable.
How to make this an outstanding pack:
Replace all the load bearing buckles (including hip belt buckle) with quality replacements - I used the Marine ILBE Repair Buckle Set available at most military surplus/supply places.
Replace the hip belt with a battle belt so you can put some gear on your hips and pouches up front for point-n-shoot camera, lip balm, etc.