Extremely comfortable. I just swapped out my old pack (4800ci and 6lb 5oz) to the Ozone (3800ci and 3lb). I couldn't believe how much easier and more comfortable my trip was compared with using the bulky Jack Wolfskin. All my gear fit perfectly for my solo overnighter. With the extension fabric on top I'm sure I could fit enough food/gear to pull off a five-day trip. This pack's suspension made my 24lb pack feel like 15lbs.