Bought this pack to take on the Camino de Santiago.  We spent five long weeks together.

On the flight over I wore the smaller pack, carried the larger pack as my carry on.  No issues with the airlines.  On the flight back I again wore the smaller pack, but checked the larger pack as luggage.

I carried a heavy load.  Had to make several adjustments during the first week to find the right fit.  Over time, the pack formed to my back and became a part of me.  The sturdy waist strap helped keep weight off of my shoulders.

Kept my valuables, i pad, meds, extra glasses, in the small pack.  If I felt the need to, I would remove the small pack and wear it rather than leave it in the open bays where I usually slept.  Put a TSA lock on it at night, and when in larger cities.

When fully loaded the smaller pack protrudes enough that a generic 55 liter rain cover really wasn't large enough.

Though probably not intended for this purpose, the compression straps that wrap around the smaller pack make a good place to carry walking poles.

The mesh pockets are inadequate to hold a .5 liter water bottle.  The bottle fits, but is slings out when you put on the pack.  I kept three .5 liter bottles of water on top and inside the pack.  That was fine with me, as when I took a break the first thing I did was take the pack off.

After five weeks of daily and extended use the pack shows no wear.  I noticed a lot of long distance hikers, particularly Americans, opted for Osprey packs.