I've been using it to commute by bike to work for over a month. My route is 39 miles round trip, I do it twice a week, working up to 3x.
The bag rocks. Here are my thoughts, good and bad.
- The zippers take some effort to open and close, but with some practice it becomes easy. I have the sense I can almost go swimming with this thing and everything inside will be dry.
- The suspended back thingy reduces back sweat better than any other backpack / bag I've ever had. It's shocking to go back to a lightly-loaded Chrome and feel the difference.
- The waist strap is the best thing ever. All the weight is carried on the hips. Very little on the shoulders. It unfortunately falls right on the top of my jersey pockets, so I usually have to work a bit to get stuff out of them. Very stable, only bounces around a bit when I'm at my fastest RPM and I have bad form.
- I usually leave the shoulders fairly loose when standing, so it's snug when I'm tucked over the bike. When I'm really in an aero tuck flying down a hill, the back of my helmet bumps the top of the backpack, it's annoying but not a show-stopper.
- I'm 6'-3", so my clothes are big, and I can fit shoes, jeans, long-sleeved shirt, socks, underwear, big shower towel, dop kit, extra jersey, extra socks, wallet, keys, etc. in the main compartment and it's still ready for more.
- The outside vertical pocket fits a mini morph, spare inner tube, multi-tool, levers, and two sets of sunglasses, and still has room. Stuff tends to collect at the bottom, but if you pack it right, it's fine.
- The blinky loop on the bottom makes the pack a bit harder to stand up straight when it's on the ground. I call it an OK trade-off for having the blinky in the perfect place when riding.
- The outer shell is tough, and holds it's shape well. It's definitely more rigid because of the waterproofing.
- The stretchy outside pockets are really high up and difficult to get to when riding, so I use them to hold extra food and Gu packets.
Hope that helps.
- It fits my Macbook and padded sleeve just fine.
- The mesh helmet thing is included. It folds into a pocket. I always forget to use it.