I bought this bag specifically for a trip via airline, something I haven't done in a while. I wanted a backpack to carry a reasonable amount of camera gear, small laptop, and accessories during transit. I didn't want a HUGE backpack that would be a burden to carry through airports or possibly get separated from during the flight. I was traveling with my parents and 6 year old daughter and photography wasn't the primary mission here.
As shown, it is holding
* 580EXII flash
* 70-200 f/2.8 II
* 24-70 f/2.8 II mounted to a 5D3
* Peak Design slide strap rolled up in the lower left
* 16-35 f/4 IS in the upper right\
* Cable management pouch with spare batteries, card reader, wired remote, cables, etc
My Canon battery charger and a 4 cell NiMH travel charger fit under the Cable Management. I believe the laptop power adapter was above the white extension cord on the left. I chose to leave the lens hoods at home for this trip but they could have fit.
The outer compartment held my small 11" Asus laptop easily. According to Think Tank, its designed to hold a 13" laptop and some 15" laptops. I checked the specs online and it looks like it will hold a Dell XPS 15 which has very thin bezels and is more the size of a traditional "big bezel" 13" model. The outer compartment also has a dedicated slot for a tablet, pen holders, and some pockets of various sizes, one that runs the width of the compartment and has Velcro closures. I used the outer compartment for things I might need while flying since it would be more accessible in cramped quarters and I didn't want to reveal thousands of dollars worth of gear by opening the main compartment in transit.
The backpack has a small stretchy pouch on the side which Think Tank shows holding a least a couple of tripod legs. I believe a 500ml water bottle would fit too. I used it for my Anker 26,000 mAh battery pack. Remember, I was flying with a 6 year old and her Amazon tablet loaded up with hours of media to fight the boredom so spare power was essential.
There is a very thin zippered compartment on top of the bag, just under the handle. This fits boarding passes (folded in half) and luggage claim tickets.
The backpack has a sternum strap and waist strap. The waist strap is removable (which I did) but the sternum strap is not (wished it was). I didn't need either as I was not hiking miles and wanted to minimize the dangly bits that might get in the way or get caught on something.
We flew Southwest so it was 737's all the way. I sat in the middle seat and stowed the bag as shown in the first picture with the short side (top) facing me. It is pushed back as far as it will go. There was plenty of room to stretch my left leg out next to the bag and I could just reach the handle to pull the bag up for access.
The bag also fits sideways and pushes back farther as a result. This would be useful should a flight attendant decide it sticks out too far in the first position, interfering with people's feet. Its tougher to access this way, but better than being forced to stow it overheard or gate check it if an attendant is having a bad day and being picky.
The backpack was comfortable enough despite the relatively thin straps. This isn't a "hike all day" kind of bag with enough capacity for a week's needs. The lack of a million zippered compartments outside keeps the external appearance clean and non-descript. Unless someone knows what Think Tank makes, they'd just see a plain black backpack.
I used the this bag just for transporting my gear to my destination. I normally don't use a backpack when shooting since they're big and slow to access gear. I took my Think Tank Turnstyle 20 in my suitcase and transferred just the day's gear to it while at my destination.