This back pack has been great for me. It is a very cool looking and functional backpack. It is light and very aerodynamic. My physics teacher actually commented out it's "aerodynamic properties" at a random time during lab. The problem I have with the backpack is that it isn't very durable. I have had the backpack for about a month and I already have a 3-inch slit/hole in the back of the backpack. I am not sure how I got it, but I think it was caused by me over-stuffing the backpack with pizza boxes. Another thing is that the backpack feels a little wide at the top of the shoulders. It's almost like it is a size too big. I don't think my shoulders are narrow, but the straps feel a little weird to me. The final thing is the backpack's space and the zipper. So, the I got the smallest size backpack of this product, and I thought that there would be more space. It isn't small, but it is far from large. I would say that it has less volume than a traditional backpack. So you can carry a textbook, small laptop (less that 15.6-inch), wallet keys ect., calculator, and a small binder. The zipper opens from the back, it will take time getting used to. Also the backpack has a weird shape, so it tends to be unstable when you lay it on the ground front first. Overall, very nice backpack. I don't regret my purchase.