I've just bought a Salomon Advanced Skin S-Lab 12 Set through Castleberg Outdoors who are a cracking company that I'll definitely be using again even though they're not close enough to visit. That may actually be a good thing, for my wallet at least.
The design team has put so much thought into the vest, to a level I don't think I've seen before. I've bought the XL version of the 2013 model which explains the red you can see.
Unlike typical backpacks, this vest design is tensioned with the two chest straps, both of which can be completely removed, or configured as you see fit. There are also two shoulder straps to pull the pack close to your body once it's loaded.
On the left (as you look) there's a small pocket apparently for a mobile phone, but it'll take a small pack or two of Kendal Mint Cake. On the right is a removable zipped pouch that'll take a few gels, and there's a spare pouch included. The two other pouches can take water bottles or food; they're 6 cm diameter and 15 cm deep, with another small pocket on the back of each.
On the right there's basically a huge zipped mesh pocket that can easily be reached with the right hand. But there's also another open-topped pouch of the same size behind it. This will take a peaked hat, or a lightweight jacket.
There are two elasticated tension straps on the side of the main compartment. These attach to the pack before the zip, and so won't prevent you from bursting the zip if you over fill the main compartment.
On the left it's the same as the right, with the addition of a whistle.
The main compartment is split with a zip, so you basically have two compartments, one on top of the other, maybe for emergency warm kit in the bottom that you don't need to get to, and waterproofs in the top. But if the zip is undone, you can get to the whole compartment.
On the outside of the back is another mesh pocket covering the whole back, which will take a full set of waterproofs.
There are also loops down the right and left side, and on the bottom so you can run some elastic between them all. I guess you could hold a helmet to the back of the pack using it.
Looking at the top, you can see the main compartment zip which allows access through the top.
Underneath that is another zipped pocket which is about 15x20cm.
Underneath that is another magnetically secured pouch which carries a foil blanket.
Under that is access to the 1.5 litre bladder held inside an insulated pouch.
The elastic loop on the left is part of the pole securing system, which you can use whilst you're moving.
So why is this pack so awesome? Well, on a long unsupported run there will be kit you need when something goes wrong, which goes in the bottom of the main compartment. Things that you may need go in the top of the main compartment or black mesh pocket on the back. Kit that you need access to whilst moving can go in any of the other pockets or pouches; food in the right hand mesh pocket, gloves, buff, headtorch, batteries, compass in the left mesh pocket. GPS, gels, phone, bottles go on the front.
Buy one, you'll not regret it.