I recently got a 1DsII which replaced my 30D. I carried the 30D in a Lowepro Primus Backpack which was a great bag. I loved the fact that I could access the camera and lenses without taking off the pack. Unfortunately, the 1Ds is too big for the side access on the Primus and I had to let it go. My old bag which I’ve been using in the interim is a Crumpler December Quarter which is the predecessor to the 7 Million Dollar bag. The 1Ds and my other lenses pretty much fill it up, but I can get away with it. The problem I have with that style of bag is comfort and security. I do a fair amount of hiking and the weight displacement on this bag is less than ideal. Also, I will be going on a trip to DC in a few months and am nervous about how easy it is to access the bag. If I carry the bag in it’s most comfortable position with the strap on my opposite shoulder and the bag against my back anyone could open the flap with relative ease and grab something before I could react. Lastly, the Crumpler has no tripod accommodation.
One major gripe with backpacks in general is accessing the gear is generally a take it off, set it down, unzip process. That was one reason I loved the side access of the Primus so much. However, on the plus side backpacks provide a great way to disperse the weight of the gear making a long hike bearable.
Another nicety would be the ability to carry additional items such as clothing layers, hydration pack, tripod, etc.
At present my equipment includes the 1Ds, 16-35, 24-105 and 70-200. For the trip I might rent a 85L. Accessories include about 8 filters, flash, and a bunch of small crap like wireless remotes, etc.
Is there a utopian bag out there? I haven't looked at the bag market for a while and am not sure what's out there?

