I tried hard to hate this hydration pack. I prefer simple packs, and at first glance, the Salomon Skin Pro 10+3 looked as if it had so many small straps and loops that wearing it would feel like being tied in a streamlined granny knot. After a little adjustment, a three-hour trail run, and a few shorter dates, however, I was forced to rethink my prejudices.
Comfort, fit, and mechanics:
This is the most adjustable pack I've met. Velcro at the top of each shoulder strap allows about six inches of play to shorten or lengthen the vest; two adjustable straps with plastic clips at the tops of the shoulders allow fine adjustments while running, and sleeves over the whole arrangement reduce chafing where straps meet clavicle.
There are eight plastic loops along the side of each shoulder strap to which two flexible and adjustable elastic chest straps attach in a variety of comfortable directions--a boon to female runners and to those who chafe at chest straps in high places.
I'm 5'2" and have a shorter than average torso even for my height, so the pack itself is still a little long for me. Even at its shortest configuration, the pack reaches past the bottom of my ribcage and almost to my hips. The two adjustable chest straps almost eliminated lateral bouncing while I ran, but due to the pack's length, vertical bounce was harder to eliminate without snuggling the weight of the pack uncomfortably against my spine. When adjusted too loosely, the pack bounced enough to bruise my back. But Salomon scores extra points here for sewing the bottom of the hydration sleeve a few inches above the bottom of the pack. That means most of the pack weight rests higher between the shoulder blades, where bouncing does the least damage.
On smaller runners, the Skin Pro 10+3 rides low.
The pack was warm, comfortable, and well-ventilated on breezy but clear winter days at mid-range elevations (4,300' to 6,500'), but it might prove to be too warm in summer simply because the vest covers so much surface area.
Packability and accessibility:
Salomon lists the 10+3's volume at 13 liters, which translates to eight packable compartments: two water bottle sleeves with drawstrings on the front, two stretchy side pockets, a hydration compartment with a 1.5L hydration bladder and insulated sleeve, a larger main compartment, a zippered pocket on the back, and, last and least, a gel-and-salt-capsule-sized lycra pocket with a small safety whistle attached to one of the water bottle sleeves. A compression zipper around the main compartment allows for quick expansion if you need it, and leash-and-loop attachments will hold trekking poles if you use them. All of these fit together into a surprisingly light (slightly less than a pound when not loaded) and streamlined shape.
In short, there's enough room here to pack food, clothes, a small camera, and equipment for a full day of trail running. The side pockets are an easy reach back if you want to stow or pull out a hat, gloves, or a small jacket; the water bottle pockets in front can also hold snack bars and a small point-and-shoot camera. That's a good thing, because getting into the main compartment requires unclipping the two chest straps, taking the pack off, and then maneuvering around and/or through the two adjustable shoulder straps to get to the main compartment's zipper.
Salomon includes a BPA-, PVC- and phthalate-free 1.5 liter/50 ounce hydration bladder and a light insulated sleeve with the pack; both of these fit into a separate, easily accessible hydration compartment that sits a few inches higher than the bottom of the main compartment. A small adjustable leash at the top of the compartment attaches to the insulated hydration sleeve and minimizes forward-and-backward bounce.
A convenient quick-release on the hydration bladder allows easy water refills without removing the drinking tube from the backpack. Once it's detached from the drinking tube, the hydration bladder is a pleasure to use: a clip slides easily off the folded top to allow quick access for refilling and cleaning. The top clip is leashed to the hydration bladder--no need to worry about losing it or dropping it in the dirt.
A quick-release on the hydration bladder allows quick water refills without removing the hydration tube from the pack.
The hydration tube itself runs under rather than over the arm and is difficult to pull back into the pack if it's too long. That's easily fixed by rerouting the tube up the side of the pack and down over the shoulder, where it attaches nicely to one of the pack's small loops.
The bite-valve locks to prevent leaks, but the lock is difficult to operate one-handed. Left unlocked, the bite valve didn't leak while I ran, although that might change as the plastic in the mouthpiece ages.
In the case of this one-size-fits-most pack, the word "fits" meets a much higher standard, somewhere in the range of "feels like a second skin." If you fall within normal human adult height ranges, try a speed date with this pack, and be prepared to fall in deep, deep like with the pack's many thoughtful details. If you occasionally land in children's sizes or have to lean down to hear people, however, proceed with caution, or investigate other packs in the same product line that are offered in XS/S and M/L sizes.