I use the Lowepro Messenger if I'm bringing along a flash and some other stuff. I like it because it isn't as bulky as many others and you can fit a lot of stuff, comes in different sizes also.
the messenger i know seems to be a bit small to fit a 5D MK3 with BG... not?
my main concerne is the attached BG. i don´t want to squash it in so thight or i could just use my tamrac.
which messenger version do you mean?
Ah,you want for the camera also, hm, yeah then no... I always carry the camera with a Black Rapid strap, and keep everything else in the messenger, I never pack away my camera.
The LowePro Pro Messenger 180AW should work for that setup if you do want to pack the camera with 70-200 attached. I have the 160AW and it might be a bit short, but the 180AW adds a couple of inches in height without adding depth/width. It's a very comfortable travel/event bag for me. Very similar (rip-off?) to the the ThinkTank Retrospective, but with better padding and a nice magnetic closure if you fold up the long Velcro flap. It's also very discrete like the Retrospective for street shooting/travel, which I really like. Not cheap, though.