Looks like a backpack/messenger hybrid, but it leans towards more a messenger bag in what it can carry. It's 20L max capacity and not just the main compartment (more on this later)Love the design and look of the bag. Looks very slick and very easy to access contents inside.Bag has very nice curves to it. The metal accents on the maglatch and top cover makes for a very attractive look.Unlike a traditional backpack, you do not need to dig your hand or arm into the bag and blind feel for items (unless you take out the flex folds). Able to swing the bag around and get items via on-body accessOrganization is also very good with the flex fold shelves, able to compartmentalize medium sized items (and camera accessories).--Shoulder Straps:Shoulder straps are thin to make it so that it's easy to swing the bag in front of you for easy access to contents from size pockets.Seeing that it's thin it dose pose some potential problems.If you ever overfilled an messenger or sling bag with heavy objects; you tend to strain digging into your shoulders over time. With this bag you have a little more leeway with double sided support, but seeing that it has an appearance of a backpack you tend to have a physiological need overfill it. When carrying this around, best to go minimal when you can.I like how there's a axial strap on a pivot that holds on the shoulder strap. Conforms to your shoulders well and feel natural (minimal stiffness) when you wear it, not having the bag's weight in on you (unless you overfill it) and moves with you as you carry it.Sternum/chest, and waist strap relieves the weight a bit, but not my much--Pockets:Bag has tons of pockets for compartmentalization. Note that pockets build off each other. Putting a lot of items in one may take away space from the other especially the main central compartment.Side flap has tons of internal pockets within it. Color coded for battery use. Has stretchy mesh so contents inside are not crushed. If you add too much stuff in internal flap pockets you may have to fold up one of the flex folds so it can zip up all the way.Water bottle/exterior pockets has a nice grip to it. Best water bottle pocket in any backpack i used in terms of securing a water bottle. Know that it shares space with 2 straps (waist strap/stow away strap) per pocket and key chain strap ("anchor link key tether). You can remove these if you like to save space. Water bottle pocket also stacks with side flap pocket making less room for central areaLaptop/Tablet pockets. Has nice curved divider for both laptop and tablet. Ideal for thin laptops like Macbooks. If you have a thick laptop it takes up space from the main compartment.Quick access top pocket. Good for putting cellphone and other frequently used accessories inside. Easily get to items you need when on the ground beside you.-Main compartment:Main compartment is not very large. Very similar space to the main compartment of the 10L sling bag when not expanded.When it is expanded from the top; make sure you tuck in the side flaps so no water will get if it rains. Even when you tuck it in, there's still a hole where water can get in, but only if you're in a rainstorm and water is coming from the sides (from heavy winds) and not straight down. Has flex fold dividers where you can rearrange via Velcro. Flex fold dividers do fold up so you can get 3 separate compartments per dividerDoes not make a good book bag. Standard size notebooks does not fit default configuration. Must remove one (center) of the flex dividers and move the top one down. Pens and pencils are not easily accessible if you have them on the side flaps as you have to unzip two zippers. You can put them in the quick access pocket up top, but it's not as organized.As mentioned before, must be mindful of items you put into other pockets as it does takes up space in the main compartment.--Maglatch/security:For Maglatch you just pull down and towards you to release. If you pull up, it will not open flapTo secure just clip it on. Very easy, no need to adjust anything as it's attached via magnetsMaglatch pocket/expansion gives the bag additional 8L storage from the already 10L (main compartment) + 2L additional pockets making the grand total storage of 20L. For reference, the Jansport Superbreak backpack (one with 1 large pocket and one exterior pocket) is 25L max capacity.Around the bag there are anti-theft pull loops to detour pick pocketersIf thieves are familiar with the bag and have a knife they still can get into the bag while you're wearing it assuming they're super stealthy.--External carry straps.Have various stowaway carry straps in case you want to strap on a yoga mat, jacket, large tripod, dufflebag, etc on the outside. Again weight can be an issue if you don't have strong broad shoulders--Handles.Love the handles on this bag. Very sturdy, solid grip when you grab onto them. Has one up top and one on each side. The side grab handles are super convenient when you have the bag beside you when it's on the passenger side of your car (you in driver's seat); just grab and go without re-orienting your arms much--Weather proof.Fabric and zipper lining are made of waterproof material. Water slips right off, assuming you're not drowning it with water. Can survive rain fall, but probably not a focused downpour, under a natural waterfall, or in the shower (for some reason).--BuildBuild is very solid with quality materials used. Has a defined shape. Difficult to compress. Sturdy, yet may be difficult to stow away under the seat of a plane.Speaking of planes; has a luggage pass-throughBag itself is 3lbs default weight with included accessories. For reference Jansport Super Break Backpack is 12oz (0.75 lb)--Closing Thoughts Very functional bag if you use it like a messenger bag, don't overload it and be mindful where you put your stuff. Convenient if you use it correctly/efficiently.Very situational bag. I wouldn't say it's a "everyday" or main bag unless you're a minimalist, use it as a quick access camera bag, or use as messenger bag with extra strap.Price tag is really high for what you get. Can be worth it overtime if you plan to use it regularly or money is not an issue.