Well-known backpack maker Osprey has made a big splash in hydration systems with its expansive Raptor line. The Raptor 10 is the second smallest among the four Raptor packs. At 610 cubic inches, it straddles the line between short-haul racer and long-distance packer. The pack benefits from Osprey’s load-lightening suspension system and comfortable back panel. It also has a reinforced reservoir: The rigid design keeps the pack from rolling on your back and makes it easy to slip it inside the bladder sleeve.