Every Miles A Memory
Expedition Leader
If just wandering around shooting and only wanting to keep a few accessories with me, I/we use the Lowepro Toploader 75 AW
It'll hold a 5D with a 70-200 (Hood Reversed) with a grip on or any of the pro bodies with their larger frame.
Since 99% of the time I'm out shooting the camera stays in my hand, the bag is really just to carry another lens/flash/accessories/Granola Bar...etc
I find this to be one of the most comfortable bags on the market and have tried dozens over the years.
Cool thing about this model is you can use a chest harness that comes with the bag to strap it on the front of your chest if you have a traditional backpack on and want to keep the camera close at hand.
Another thing I like about the bag is I can strap it on the deck of the kayak and keep a body with lens attached for quick access while paddling.
Not the best example picture, but you can see it latched to the deck
It'll hold a 5D with a 70-200 (Hood Reversed) with a grip on or any of the pro bodies with their larger frame.
Since 99% of the time I'm out shooting the camera stays in my hand, the bag is really just to carry another lens/flash/accessories/Granola Bar...etc
I find this to be one of the most comfortable bags on the market and have tried dozens over the years.
Cool thing about this model is you can use a chest harness that comes with the bag to strap it on the front of your chest if you have a traditional backpack on and want to keep the camera close at hand.
Another thing I like about the bag is I can strap it on the deck of the kayak and keep a body with lens attached for quick access while paddling.

Not the best example picture, but you can see it latched to the deck