i really like this bag, ive had it for a bit now, and mostly use it for my laptop, but can also fit my rain jacket, lights, notebooks, spare tube, pump, clifbars and other flat small things in it... it fits really tight to your back, and is very comfortable, the pockets are well placed and very large... and in many ways are more useful than the large section... which im not saying is useless, but the biggest benefits are the pockets, which function like jersey pockets and are extremely easy to access. i have 2 very large bags, and ortlieb and a bedlam that i use for courier work, and a small baileys and this bag that i use around town, and for doing dya long riding around across or to the next town where you need to bring a few things, i like this better than any messenger bag... its usefulness is when you wanna ride not too far, and not too heavy... it looks good, feels great etc... im a rapha nut though. it has its place...