David,

I settled on a F64 BPX pack. it swallows the Arca/Swiss camera, bellows, rail, darkcloth, film and lens hood in the large bottom compartment. Lenses and fiulters fit in the top compartment. Side pockets allow for extras and or for lashing a tripod to it. Minor point: the two compartment are separated by a bit of padding. So the camera bears no weight except that of the lightest objects, such as extra bellows and lens hoods.
I have tried Kelty packs, stronboxes--fine for level surfaces!- and other combinations. The F64 works pretty well, and costs a lot less than the pack that dykinga uses.
I don't pack 50 llbs for overnight treks. Maybe then I would opt for the Lowe. Maybe then iIwould opt for a hummer!.

Bob