I bought the large version of this (13 inch) for my Madewell Transport Tote. I absolutely love it. It fits all my stuff (wallet, Lily Pulizter Calendar, glasses, pens, makeup case, iPad, and my MacBook Air (in its sleeve on its side.) I don't think it's a full 13" long, as there is room to slip my water bottle where it ends and the tote wall. But that's ok! Because that space makes a nice spot to nestle a water bottle without it tipping over.

Without the organizer, things are just a jumble in this tote. Now I can find what I want. The side zip pockets are perfect for storing loose papers until I can get home.