That's a centerpull brake. Not a V-brake. Ignore anything about V-brakes regarding this bike. The "Bike Touring Review" reference you're looking at is too new to acknowledge these old but decent brakes.

Centerpull brakes are old-skool, long-reach, wide opening brakes. They can have plenty of stopping power so long as they're adjusted properly (true of any brake). Kool-stop pads and alloy rims help a lot.

Centerpull brakes like the one you show have the same lever pull as sidepull caliper and cantilever brakes. So you can use the same brake levers for the centerpull in front and the sidepull in back. Use the Tektro RL340's for your bike, the RL520's are the ones for V-brake (aka linear-pull brakes), which your bike does not have.