I guess I'm a wimp compared to most men. I weigh 200 and am an in shape construction worker, but still would hate to carry 25 lbs. on just my shoulders. Odd, since I haul 75 lb. bundles of shingles up ladders on one shoulder and carry 90 lb. bags of Portland the same way. The climbing packs work for me, as long as they stay under what I said. If I want pain, I'll just stay in work. They are designed to carry comfortably and without sway, otherwise it would be hard to climb with them Mt. Hardware makes some nice ones, besides the excellent Patagonia I mentioned. Climbing packs sans hipbelt are easy to find and are designed that way. My wife and I did an overnight on the AT with one daypack, but we were doing an extreme ultralight test. It was OK, but I prefer more security and comfort.