I'm looking to purchase a Tom Bihn bag for my son who is starting high school this fall. First off, he needs a backpack that can carry a great deal of "stuff" back and forth from school. I'm talking books, folders, school supplies, a 1L SIGG bottle, lunch, etc. He will also be using this bag as a portable locker of sorts throughout the day so it has to have some sort of organizational capability. Which Tom Bihn backpack will do all of the above, and then some?