I currently have a Minitrekker AW and it can hold my 20D with a 400L attached and also has room for an additional 70-200 IS lens. However I will be trying to use my camera in dusty conditions and thought it would be really convenient to bring along my 300D for 70-200. That would allow me to have two cameras ready all the time and not have to worry so much about dust if I tried to swap lens.
I like the Minitrekker because it is perfect for airline travel and holds almost all of my gear. I might have trouble trying to stuff the 300D body in there but I can probably make it fit. This trip will be a little different because we are moving around on moutain bikes and I will likely only need two lens and can leave extra equipment back at camp.
Is it worth trying to find a padded camera bag that meets these criteria? Or should I just bring along a second standard backpack and some padding to keep the cameras from knocking together too much?

