"The Feds have a fetish for loyalty..."
I've got the Kata DR-467 you mention. In it I put my 17" MBP, a Nikon D5k and two (kit) lenses. Comfortably it holds as well both chargers (camera, computer) extra camera batteries, a fold up reflector, moleskin notebook, Slik Sprint Pro tripod (not always, but when I want it it fits well), a full size mouse, an iPad (not terribly well but you can squeeze it in with the MBP), and some other misc stuff. There is room left over in the top compartment for, easily, a jacket and, say, some food.
I used to carry this with me everyday everywhere for about 6 months (have your camera with you all the time). The bag is entirely fine. YMMV. I stopped carrying it because, as others have pointed out, it's pretty heavy. I never cared enough to weigh it but it is heavy enough that I just stopped wanting to deal with it.
tl;dr Kata bag holds a ton of shit. Mine held up well to everyday use for 6 months.