I have a very small tamrac backpack. It barely fits my 30d, 28-135mm lens, 28-90mm lens, 70-300mm lens, and my rebel k2, with a few filters, film, lens caps, and a few other small items. It's really uncomfortable to walk around with for extended periods of time. It's terrible for quick access. I have to stop and find some where to set it down to take things out otherwise everything will come flying out and i can't afford that. I need a bag that will allow me to carry a decent amount of gear comfortably, and have easy access to all of the gear inside. I've tried walking around with both cameras on so i wouldn't have to change lenses but that is very uncomfortable after about an hour. does anyone have any suggestions.