I love my Kata R102 - had it for 2 years, holds a ton of gear, excellent comfort design for long distance traveling, variable tripod mounter can be put on either side or centered on back, and practically bulletproof in design (Kata does everything from journalist pro gear to bullet proof vests and Israeli military stuff!). ; I typically use it to transport my camera plus 7 lenses, flash, cleaning kit, filters, all cables, chargers, and netbook. ; A primary selling point for me, that I had much trouble with on some other backpacks, was the ability to configure the inside compartments so I could carry my camera body with Tamron 200-500mm lens mounted (or 300mm F4). ; This is one of the few backpacks I found that allows me to do so, and to open up two compartments so I could carry both long lenses, one mounted long lens, or one smaller mounted lens and the large lens to the side...maximum versatility in moving the compartments around inside as needed. ; And if I get a full frame body or vertical grip, that will fit in the bag mounted too as the center chamber is tall enough to accomodate full frame VG bodies.
It's worth a look. ; Craig here got one too, and seems to like it.