The bag is smaller than I thought it would be. I bought it to use with a Canon 300D, 50/1.4, 100/2, 70-200/4L, and the 18-55/3.5 kit lens. This kit will fit, but it's slightly more cramped than I'd prefer. Since then, I've moved to a 40D, 28-135, 10-22, 50/1.4, 200/2.8, 1.4X TC, and a 430EX flash. This is really the maximum for this bag. One or two middle lenses less would be ideal.
To mold to your hip, the F6 has to have two open spaces in the center partition. It's really designed for people who have some other bag to *store* their gear and want a quick working pack for travel. It's not supposed to be full. If you've got a big superzoom (100-400, 70-200/2.8) or an equipment list similar to what's above, move up to the Domke F-2. It's nearly as discreet, but a lot more spacious.
The only interior layout this bag has is a four-part partition held in place by velcro. If you remove the partition, it's just an empty space. On either side of the partition are larger areas that, in my case, hold the 430EX and the 200/2.8. The partition itself was designed for manual equipment: long and thin lenses, and film bodies without deep grips that could be slotted where I have the prime and the flash. That's Domke's graphic, anyway. It's both difficult and inconvenient to fit a DSLR in those areas, though, and you have to remove the lens.
The better solution, and the one I was forced to use because I have more equipment than before, is to have a moderately heavy lens like the 28-135 mounted to the camera at all times. Then you just put the camera face-down over an empty partition space. The malleable nature of the partition and the weight of the lens hold the camera in place, with the added bonus of freeing up space and having the camera ready to shoot.
While it's also possible to do this with the 50/1.4, the bag starts to feel slightly top heavy, so you'd want to have at least one side of the cover clipped to keep everything secure.
BUILD AND FEATURES:
There is no side padding on this bag. It conforms to the waist better for that reason, but don't buy it if you're worried about bumping your SLR. The front pocket, bottom pad, and the partition do keep the lenses in the middle decently protected. If not for this light padding, the bag would not hold its shape. Even as is, heavier loads cause unused pockets to compress in on themselves, so if you take a lens out, it may take a bit of fiddling to get it back in.
The two metal clips stink. They're small, difficult to unclip, and tend to knock about into your lenses when not in use. There's no easy way to remove them, but if you're willing to reduce the resale value of the bag, you can replace them with superior mini-carabiners.
As shipped, the F-6 is not waterproof, but it can be made water-resistant with the same aerosol waterproofer you'd use on leather boots. I put two coats of Kiwi "Camp Dry" 13% Silicon water repellent on my bag two years ago. A water puddle on the cover will still bead for a full minute before it starts to wet the canvas.
People tend not to assume that this Domke is a camera bag. On two occasions, I've been able to enter a sports venue without the ticket-checker bothering to look for equipment. While the front pocket is not padded, it can hold quite a lot. I was able to "hide" a 70-200/4L inside with little change in the bag's outside appearance.
The rubber embedded in the strap is great if you wear the bag like a purse, but I loop the strap over the other side of my neck and across the chest. When I do that, the rubber makes it difficult to shift the bag in front of me without binding my shirt. No big deal; there's no rubber on the opposing side side of the strap, so I just turn it over.
If you fill the bag with my revised equipment list above, it'll feel like a brick on your side and will cause your shoulder to ache after a few hours. I bought the mail carrier strap to mitigate this problem, but I find myself rarely using it. The padding on this optional addition is less soft than it appears in the picture, and the whole item feels bulky. A wider and less-thickly-padded generic alternative would probably work better.
There are comparable Chinese rip-off bags by Mekko and Safrotto. They're high quality and cost about 30% less than this Domke bag. I bought the Domke because the olive green color wasn't available in the others, and the Mekko bags in particular have too many ostentatious logos I didn't feel like removing. Otherwise, they're worth a look.
The biggest competition for the F-6 is Domke's own F2. While the F-6 is handsome and functional, it doesn't have much room to grow. The F2 offers significantly more space, though because the unused portions collapse on themselves like with any canvas bag, it doesn't look or feel much larger than the F-6. Had I known that I'd expand my kit to the extent that I did, I'd have chosen the F2.