I pretty much have to agree with other reviews that talk about the small size of this bag. It's definitely quite limited in what it can carry....but it does work for me in some situations. It *does* hold my Canon 40D with Tamron 18-270mm super-zoom attached along with my 540EX flash and a extra 50mm lens, so would be a reasonable bag for me to use on trips when I am not able to bring a selection of lenses with me. I am not a person that can carry much equipment with me in the field due to physical problems, so I really need a bag that is comfortable and can handle at least this amount of equipment. I do wish the interior dividers and velcro had a few more optional placements, you're pretty restricted in how they can be placed.
You'll find many, many interior compartments and stuff hidden away in this bag, including a nice rain cover for the camera on the inside, and for the entire bag on the outside. The tripod holder flap can be tucked inside, as well as the additional waist strap. There almost to me seem to be *too* many compartments. I don't need so many that I end up having to remember where I put what item and unzipping a dozen pockets to find it. But I'm sure a lot of photo geeks loves that kind of thing.
While I do love the sling design in terms of it helping to relieve some of the weight that is so problematic for me, I do have to add that it's not the easiest (or most flattering) thing for many women to wear, particularly if you are, umm, well-endowed shall we say. I basically have to either push the strap up in which case it is practically strangling me, or move it slightly down which umm, pushes other things UP. The second strap which is described as a "waist strap" actually comes up creating sort of an X in front, just making the whole thing look even worse (like a huge push-up bra worn on the outside). I'm not sure there's really a good solution to this, but women might want to try one of these in a local camera store to see how much it bothers them before purchasing.