Ian Rosenberg wrote a review of Black Diamond Mercury 75 Backpack - 4577-4700cu in on July 15, 2012
This is a phenomenal pack. From top to bottom Black Diamond got every detail right. I just spent some time backpacking in the Sawatch Range in Colorado with the 75 liter version and this is what I took away from the trip.
-The suspension system does everything BD says it should. I was carrying 50-60 lbs and the entire load was distributed comfortably into my hips with no chafing or squeezing. The back panel grants great air flow and the hip belt and shoulder straps are both well padded and anatomically shaped. The freedom of movement the pack allows made walking feel much more natural; I could hardly tell I was wearing a framed pack. It also made using poles much easier on my shoulders since the straps would extend with each swing of my arm.
-The organizational features are well thought out; It's essentially a single compartment pack, but the extra pockets BD included are useful for small items that would otherwise float around in the main body of the pack. The lid is spacious and has a pocket on its top and bottom. The interior mesh pockets are also easily accessible and sized just large enough to fit a shell or several pieces of small gear.
-The pack is built tough. The fabric is very wear resistant and the zippers and buckles all operate easily and are solid enough to really pull on when you're cinching down the pack.
-The pack also sizes down very well. I used it as a summit pack with only my ten essentials and extra water and it was able to tighten down without seeming awkward or bulky
I would highly recommend this pack to anyone who is looking for a piece of gear that handle anything from day trips to extended backpacking trips comfortably and elegantly.