Last night was the test drive of the 65+15 liter backpack (it's huge!). I loaded 17 kg of junk (inlcuding a few bokks) and went for a one hour walk. First on the flat road along the Moselle river and then up the steep hills amongst the vineyards. The backpack felt great. It sits on the waist and barely feels to touch the shoulders, it pulls them back a bit, only enough to support the pack vertically. It should be fine to carry it for longer periods! 180 euros well spent!