There's a reason that more professional guides use this pack than any other pack on the market. With capacity that will rival - or even exceed - a lot of vests, the Waterdance is considered the "ultimate" lumbar pack, with its two zippered main compartments and signature "zip-down" fly bench. Need to bring an extra spool and that large streamer box, in addition to everything else? The Waterdance devours it faster than an egg burrito on the way to the put-in.
The Arroyo Chest Pack is big enough to fit a nymph and dry box, but small enough to be utilized as it's meant, up front and personal. Nevertheless, if you have a hankering to move fast, engage the hip straps to transform it for lumbar use. Despite its compactness, there is plenty of space for flies and tools, and has a zippered front flap with replaceable foam for bench work. Stay nimble.