Love this bag! I have back problems and travel a lot for work- so I needed a work bag that was light weight, functional, and wouldn't cause pain.  This bag is a  bigger than a small backpack, but I would say a smaller medium-sized bag.  My laptop is 13.25" x 9.5" and does not fit in the laptop sleeve, rather I have it at an angle across the main area of the bag.  If only it were an inch wider and taller..... That really is my only complaint.

Pockets are simple and useful.  Front big pocket holds a wallet, phone, gum, and other frequently used items.  Front small pocket is too small for a smart phone, but perfect for headphones and car keys.  Inside big zipper pocket is deep and wide, I use it for charger cords and small technology accessories.  Inside are two slip pockets perfect for putting pens and business cards in.  Inside also has a laptop sleeve pocket, it's too small for my laptop so I can't really give a quality review on that pocket.

The back of the bag has the loop thing to slide over your roller suitcase handle.  Works fabulously!  I would imagine, however, if I had a laptop in the interior sleeve that the loop might be harder to get over a suitcase handle as it would have a hard side.  Make sense?

Travel: Fits great under the seat on an airplane AND isn't a big bag that hits all the passengers seated as I walk down the aisle. Fits perfectly between my feet in cabs or on my lap on subways. Sits up well on the floor next to my seat at conferences.  Doesn't hang well on the back of a banquet chair.

Has a great polished professional look.  Marine has been a fabulous color choice (I had wanted black, but Marine was on sale), I'm very happy with the color.  The interior is a light color, so it's easier to find things inside.  My city does not have a Tumi store, so I've been visiting Tumi stores in airports to find one that will engrave the tag..... still no luck.

If you want a bag to carry the basics, and keep you from over stuffing, then this is the bag for you!  If you like to pack a little more than the basics, go for the size up with pockets on the side (I think it's roomer inside too).