The previous version of this backpack was the best bike commuting pack I have ever owned. I put more than 6,000 miles on it before it broke. Osprey offered me this newer version as a warranty replacement, which sounded wonderful-- a brand-new version of my favorite pack! Unfortunately, this pack is a disappointing downgrade. The worst is the redesign of the mesh back-- the new mesh is so soft and flimsy that as soon as I'm on the bike, it squishes flat and puts my back into direct contact with the bag. The old version would keep the pack off my back, letting air in between. Worse, the new pack has a flat pad under the mesh. There are no bumps or ridges that would allow a little ventilation when the mesh is compressed. This is supposed to be the key feature of this pack, and it just plain doesn't work. The old version was wonderful, but you'd be better off skipping the mesh for a simpler pack. The waist belt has been reduced from a two-inch strap that could support some weight to a one-inch strap that is uncomfortable if tightened enough to support much of the load. There are two large pockets in the front, but for some reason, the pockets are connected by large "vents" inside the pack. If you put a spare tire in one and an extra shirt in the other, your extra shirt will smell like a tire even though it's in a separate pocket. There's no retention for extra strap length. If you do buy this pack, make sure you grab a bunch of little elastic loops-- otherwise, the straps will whip you nonstop on your ride. The waist belt and shoulder straps have elastic that lets the pack bounce unless you tighten them down uncomfortably, but for some reason the sternum strap has none-- so you have to leave it loose to breathe. One of the useful side zip pockets is now a bottle pocket you can't close. It's a bike bag. Bottles will be on the bike. It's not all bad. The pack will stand up on its own for loading, which is great. I just wish the rest was great, too.