I just bought my second Mountainsmith Day pack, so that I don't have to constantly transfer my work & around town stuff out, and my biking or hiking gear in! This bag is a wonder. As another reviewer said, you can put a (up to 14") laptop in here easily, as well as a load of other stuff. I can't get on a plane without it. It is incredibly modular, and converts from being an around town "purse," into a rocking, well-supported, ROOMY lumbar pack (no one else's compares with this size), and with the suspension system of a full-on backpack to support it fully loaded. When empty, it is also totally compressible. Very smart design. I can't rave enough about this thing, which is why I needed two. By far the one I have was getting more use than all the other bags I own combined.

So the *one* thing Mountainsmith could improve upon is the comfort of the removable shoulder strap's pad. The shoulder pad could be a little more robust... as it currently stands, when the bag is heavily loaded and you're using the should strap, the strap can often slide off and awat from the padding, leaving all the bag's weight supported by just the bare strap on your shoulder. Not the best. BUT.... that is IT, this bag is otherwise perfect. And, they've been making them for a long time. Nice to see a manufacturer leave something alone that works well, as this bag does.

Why use a slim backpack when you can use this! 1150 cu.in.!!!

This is bigger than most daypacks and puts the weight where is should be - on your hips, at the center of your gravity.

Plus, this lets your back breath.

If you do pack this full, try out the strapettes, which act like backpack straps, but are more comfortable allowing breathability and weight distribution without hunching over.

I'll never go back to a backpack again.

I was worried that this bag wouldn't work to carry around my basics and my 13in Macbook in town and be available for any day hikes, but my fears were laid to rest. This bag fits way more than I thought it could, and the layout of the pockets make it very easy to keep organized.

This bag rocks.

I have owned my Mountainsmith day pack for close to 9 years and haven't had any problems with it except the waist buckle had a chair leg put on it and it cracked. I should have been more careful; I'm sure Mountainsmith would help me out with a new buckle... I'm just too lazy to call. Now I just tuck the buckle behind the back pad for protection. The hidden pocket back there has come in handy on more than one occasion too!

This pack is big enough to carry my books and laptop for school, and small enough that it doesn't cause problems on the bus or train. I'm a big fan!