I have the 3N1-20 and 3N1-33 for backpacks and some no-name bag when I want to go small. The Kata backpacks are great. To me they're about as close to perfection as a photography backpack can get. Lightweight, easy to organize, and can store a bunch of gear. The 3N1-20 has been to Hawaii, upstate New York, and many, many points in between. The 33 has been to just about as many places. It's small enough to fit under a seat in a plane yet large enough to hold a 70-200 IS II attached to a 1DIII.