I've got one of their small bags to hold a Leica system, and it's great.
But IMHO there's a conceptual problem with their large airport backpacks. They need to take at least one of them -- like the Airport International -- and reduce the camera carrying space and add a separate segregated compartment for personal travel gear -- tickets, glasses, cell phones, iPod, car keys, batteries, medicine, notebook, pens or pencils, earphones. Their current larger designs simply let you cram in more camera gear, which is fine, some people need that. But more people, I think, would like to carry one bag on-board that would have space for a modest system (say, two pro bodies and four lenses, a charger), a laptop with a charger (almost a necessity now) and then that personal space. Their International has the space for that, but not the configuration to carry the personal stuff. That needs to be in a separate zippered compartment. It would also be nice if the pack had some external quick release straps that could be used to strap on a jacket. This is one-bag thing necessary because more and more places allow you only one bag, sometimes on an at-the-gate basis -- security lets you through, but then you get to the gate, and the steward tells you that the bins are filling up and that you'll have to gate-check something. That has happened several times on my last few trips.
Something else that would be really cool would be a sophisticated charger that could charge everything. Or a camera battery that could be trickle-charged with a USB line, like an iPod.