The Wild Country Revo is the first bi-directional assisted-locking belay device. That sounds quite complicated, so to put it more plainly and simply, it's the first assisted-locking belay device first which allows the user to load the rope in two directions, meaning it completely removes the chance of user error when orienting the rope in the device.
There's no need to learn new belay technique, as the Revo operates just like a tube-style device. The difference is the assisted-locking mechanism. When the inertia reel spins at a speed of 4 m/s, usually caused by the fall of the lead climber, the device locks the rope. This speed isn't slow enough that the device will repeatedly lock when paying out rope quickly, and even if it does, there's no need to let go of the rope with either hand: simply pull the braking rope down to release the lock and continue belaying.
The Revo is a great option for beginners looking to learn proper belay technique with the added back-up of assisted-locking should they make a mistake, or any level climber wanting a return to proper belay technique.