I have a Cargo Large and I have to be honest, is the worst bag I ever owned.
In my life, I'm a "bag-aholic", I owned a lot of laptop bags, Tumi, Timuk2, Tucano, Burberry's, Victorinox, Samsonite, etc. and everyone has something missing (the Tumi is close to perfection anyway). I've bought the Waterfield Cargo just to try it and, again, is the worst bag i ever bought
I use it with a MBP 15" and I cannot really understand the project behind this bag.
Is big, but nothing fits in. There is no place for a paper notebook, the pouches inside are too small to fit anything, the buckle gets entangled everywhere and opens itself, the front area has a so weird shape that is impossible to put anything inside safely, is heavy, badly balanced, bulky.
Also, the outside fabric is slippery, when you wear it, it cannot stay put on your shoulders.
I can write a book on how much I'm dissatisfied of this bag.
To me are the worst 300 bucks ever spent
According to my experience, I'll advice to look for something different.
For me, if I need to buy another messenger like bag, I'll stick with Timbuk2 or go again with Tumi (even if it costs 3x/4x the Timbuk2).
MB