Comments about Pelican Pelican PCS-180 D'Exec Series Camera Tote Bag, for SLR's or Medium Format Camera Outfits, Color Black:

It's great if you din't have too many lenses. Right now I only have a nifty fifty and the kit lens that came with my 350D. I could add one longer lens (eight inches), a short lens (four inches), and a flash about the size of a 430EX, or another longer lens in place of the flash and short lens. The camera and attached lens are easy to get to, but unless you have all the top flaps open it takes a bit to access anything else in this case.

One thing I really like is it's build quality--very thick and heavy fabric. I have been out in some major rain and the inside does not even get moist! The one nitpick is the front access zipper sticks, but I don't use it much, I have it arranged for top access.

It is not the most comfortable bag in the world, but it isn't aweful either, I have easily carried it on 6 hour hikes with only slight back and shoulder aches.

Too be specific about what it can fit:
Canon 70-300mm IS would go in with a
50mm/1.8
100mm macro
Flash or 28-75mm

Side pockets could fit a flash or another lens, but they are not padded as well. Have not attempted to try tripod straps, they seem like they could carry my tripod with ease, but getting the tripod in is another story--would work great for a monopod.