Thanks for the advice.
Barry, that F3-X looks just about perfect for what I'm after. I may well go exactly that route.
desertratt, I completely agree with your thoughts on the matter. I'm a fisherman more than a photographer, and I've lost count of how many packs, vests, boxes, etc. I've tried over the years. It's even to the point where I prefer different systems for different fishing situations (large or small fish, streams, big rivers, etc.). With this experience in mind, I'm just hoping to gather as much information as I can, and hope that I have a bit more luck in my search for the perfect system with cameras.
MattKing, I actually use and love a sling bag for fishing...I'll have to explore my options in them...