Graham Parrington wrote a review of Sterling ATS Belay and Rappel Device on March 8, 2016
Familiarity: I've used it several times
This device impressed me in wet and dry canyons. I like the small biner hole keeping the device in position, especially after rapping into deep water and trying to get off rappel while floating or treading water. The versatility and ease of use for rappel and lockoff is fantastic. Nice to have friction options for different weights, ropes, and conditions. In narrow canyons the horns do snag/drag, but clipping the outer hole to the nearest harness loop keeps it out of the way most of the time. I would not use this as a primary belay device, however, as it feeds rope slowly. It works ok when progress is slow, and holds a fall/rest easily.