The Yates Rocker works very well within the manufacturer’s recommended uses. I have found it to be a good belay device to bring up a second in that it offers a dynamic grab, does not chew up the rope sheath and works well with 8 mm icy ropes. It’s not as easy to belay a leader with it but it’s workable with practice. It is also handy as a rescue ascender and a lightweight and useful part of your crevasse rescue bag of tricks.

Chossdog gives it 4 tail wags

I own this unit and have found it to be generally useful for the kinds of glacier travel and mountaineering projects I have undertaken in the last several years. However I think it’s a better GPS than a FRS-GMRS radio transmitter. In 2001 I used this unit to help coordinate the helicopter evacuation of a sick climber off Mt Rainier’s Kautz Glacier route and at the time would have liked the transmitter to have had a bit more “poop”. Conditions were line of sight and well within FRS range so I was disappointed that the transmitter was not as punchy as I would have liked. However the helo evac went off without a hitch and the climber recovered. For cold weather jaunts put lithium batteries in this puppy. It lightens up the unit to about 10 oz and works well in conditions below 0 F.
BTW, don’t use this unit (or any other GPS for that matter) to attempt to negotiate an open crevasse field in a whiteout. No GPS is that good. Probe the area, wand your bivy site and hunker down until conditions improve.