Great fit, great look and decent performance. It breathes reasonably well, sheds a light rain or snow well, and makes a nice medium weight layer for the rest of your system. If this thing had pit zips it'd be just about the perfect soft shell.

Man, do I love this pack. It's just the perfect day pack for every outdoor activity I've thrown at it, regardless of the season. In summer it's got more than enough room for any gear and supplies I might need for a day on the trails bagging peaks. The aircore really does work quite well... keeping the air between you and the pack moving. Super comfortable pack and the compression straps do a nice job of getting you an evenly distributed load when you're not carrying a lot of gear to fill the pack out with.
If you're hiking far from available water sources in the summer, this pack will easily carry 7L of water without really putting much of a dent in the main gear compartment... you can put 1L Nalgenes or Sigg canteens in each of the side stretch pockets, a 2L camelbak in the interior hydration sleeve, and a 3L camelbak in the aircore venting area between the pack and your back.

In winter I've managed to fit all of the following in/on it and it carried it all very comfortably: 2L camelbak, 1L Sigg, hat, gloves, fleece mittens w/ shells, balaclava, rain shell, extra mid-layers (top and bottoms), down parka in stuff sack, food, first aid kit, SPOT, compass, maps, extra socks, crampons, trekking poles, MSR snowshoes, and my emergency kit (headlamp, fire starters, Gerber, etc). And probably a few other things I'm forgetting. It just swallows gear.

One important thing to remember... this is a piece of technical gear.... not a book bag. It doesn't fit your laptop because it's not supposed to fit your laptop. Laptops aren't considered 'packable'. There's plenty of great book bags and days packs available that will. But this isn't it.