Just thought I'd share a 2-bag setup that some might find useful. The search for the perfect bag(s) seems to be never-ending, but at the moment I'm quite satisfied with my setup. So here it is:
Need #1: I needed a bag I could use for city walking, something a little discreet (doesn't shout "camera in here!"), and not a backpack I'd have to take off to access gear. I've been through a LP AW 200 Sling, Crumpler 4 Million, and a NG Explorer shoulder bag...none were quite right. I'd also like the bag to double as an every day messenger if possible.
Need #2: I needed a backpack that could accomodate photo gear AND personal gear at the same time, as well as carry a tripod. When hiking, I use a Cotton Carrier on front, with a backpack behind.
Gear: K-7 (sometimes with grip), DAs 12-24, 17-70, 55-300, 15/21/35/70
Solution: Timbuk2 Classic Messenger Small...tough material, waterproof lining, just right amount of pockets, great size for walking around a city and sticking under the airplane seat in front of me, leaving me room overhead for my travel backpack (I never check any luggage). One problem: no padding for camera gear, the bag is basically a shell...
Solution 2: Kata dr467i backpack...meets all of my above backpack requirements, has reputation as a quality product, and (super important) the padded camera compartment is removable...
and it fits perfectly in the Timbuk2 messenger...PERFECTLY. (I think it would work great in the medium messenger too, but might float a bit in the large, not sure.
Just after I bought this setup, Timbuk2 came out with the camera messenger. It MSRPs for about $50 more, money that could be spent on the Kata on ebay.
Anyway, after having it a couple of months, it works great. If someone else has the same requirements, I highly recommend this setup.