The new The North Face Flight Trail Vest is pretty damn awesome. Flexible and stretchy fabric allows for a tight, but forgiving fit, much like the Salomon SLAB 5L packs that I've come to love. The pack is durable, but can run super hot. All in all, it's been my goto grab piece of kit for longer training runs over the last few months, falling just behind the Salomon as one of my favorites. Solid pack, very recommended!
What is YOUR favorite hydration pack for longer runs/races? Let me know in the comments!