The Lowepro Stealth 550 AW is one of the largest bags we own, and addressed the problem of carrying around a Canon EOS camera with lenses and macro accessories which formed the core units of our product photography. As we expanded more and more into this area, it was inevitable that the gear requirements expanded along with it. Canon gear is by no means small when compared with much of the other kit we have, so it soon became obvious that we needed something big to transport it in.
It can be a liberating experience to leave most camera gear behind and travel very lightly with just one body and a couple of lenses. Arguably extra lenses or other small items can be stowed in coat pockets, but for those of us who like to keep gear in dedicated bags, there are a plethora of small, well specified models to choose from.