Scott in NYC wrote a review of Petzl Reverso Belay Device on June 13, 2003
I've used this now for ice climbing and canyoneering. On the ice, I used it primarily for belaying, and this always works great, no matter how wet the rope is or how frozen it is. In the canyons I used it primarily for rapping, and this was on 9mm double rope, which the reverso is great for. It took me a while to figure out a smooth method of getting it on and off the rope without risking it falling off a 200' high cliff. The trick is rotating the device 90 degrees while taking on/off - it's all about opening the biner to insert or remove the sope, while quickly closing the biner still on the device. With little maneuvering room and often cold, wet hands, even with gloves on, a slip might mean your device is gone. I love it. Simple. Effective.