Bought this for my Canon 40D and 17-85mm IS lens, fits perfectly either lens in first, LCD screen first or camera in sideways. I find the last one best as I can pull the camera out and the handhold and shutter release is immediately in the right place; this also gives enough space to roll up the shoulder strap. Space for a spare battery or two, two memory cards (the 40D uses Compact Flash), and probably a couple more small things as well. But dont expect to get any more in, this bag is for a dSLR and small/medium zoom lens.
Well padded, and decent zips providing a large opening. The rain cover had me fooled for a few hours though; it is tucked away and the manual didn't make it clear what and where it is. The cover comes out and protects all of the bag but not the back; can be a bit fiddly to get on and off especially as the loops for the strap have to go through holes in it. That said, it's perfectly up to the job of keeping probably a £1000 worth of camera dry when you get caught in the rain.
If using the camera a lot whilst walking about, I got into the habit of unzipping the top most of the way, then the camera (whose shoulder strap is also around my neck) sits neatly just in the bag but readily available; at least then there's two straps taking the weight and the padding of the bag protecting the camera and lens. I hardly notice the camera is there sometimes.
An excellant buy and highly recommended. I bought this at a high street shop as needed in a hurry, but did pay (a fair bit) more than Amazon are selling it for. At Amazon's price its a bargain.
Update: the AW suffix shouldn't be taken to mean 'ALL' weather. After walking for three hours in constant rain (isn't the Lake District lovely in spring/summer?!) the inside gets wet/damp and this does transfer to the camera. The lack of plastic cover for the back as previously stated may affect this further. This bag therefore isn't completely weatherproof but would be perfectly okay for short showers etc. If you want a waterproof bag for all weathers then perhaps this isn't quite up to the job and the hard plastic type with seals should be considered. That said, if you appreciate the bag's limits then it's still a top class item that is well capable of protecting £1k of camera and lens.