I have to admit being slightly bemused by this thread. I have never bought a 'camera bag', because I tend always to find things I don't like about them. Usually the look, and often too much velcro.
My strategy has always been to just get a bag I like, currently a couple of Manhattan portage book bags in two sizes, and then buy loose padded inserts from tenba or domke. This way I can precisely choose the insert to suit my gear, and as I usually have some space left at one end of the bag, I use that for things like extra film, a lightmeter, a notebook. If I am just out shooting, I use the small bag, and if I have other things I need to carry, like a book, a laptop, or a video camera, I can just move the inserts with the gear in it to the larger bag. Sometimes (shock horror) I go somewhere without a camera, and I use the same bags, without the inserts.
It gives me a lot of flexibility in use, but it also means I can buy any bag I like, not just 'camera bags'. I also find it more 'stealth' than a black camera bag, as most people would not expect that I have a camera on me.
Besides the inserts I also use op-tech neoprene hood covers ( I suppose they are designed for slipping over slr lens hoods). The smallest size is perfect for protecting RF-lenses. I tend to stack a couple of lenses with hood cover into a padded insert, but also sometime loose in the bag.