I should add I like the f64 packs too for their light weight and low bulk relative to other dedicated photo packs. However their suspension system is simple and IMO not adequate for long treks with lots of weight. For those situations, I use the large f64 as the insert for my Dana.
Here is a shot showing the two combined -- that's the f64 Large pack and a Gitzo 1325 pod with Arca head for size relation. The combined weight of those two packs is 9 pounds (4 kilos) and is less than what a Lowe Super Trekker weighs by itself, yet it will carry a lot more equipment a lot more comfortably:
Cheers,
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