ivarwrote a review of DMM Revolver Carabiner on March 6, 2017
Familiarity: I've put it through the wringer
Works very well in a crevasse resque system, at almost no weight penalty. I much prefer to use the non locking version as the gate on the locker is quite small. I use a Minitraction on a master locking carabiner as first pulley, and as many Revolvers as I need to get a mechanical advantage. If the non lockers fail, it will only slip for the lenght of the pulley system or the Mini will catch it before that even. The revolver works better than a Petzl Ultraleggera because the rope can't miss the pulley, it's lighter than a Grivel Roller and much easier to rig than a separate pulley. They are pretty strong, and work ok as a normal carabiner.
Only dislikes,: it doesn't fit a Ropeman or Tiblock very well so I need to carry an extra carabiner for that or use a prussik instead. Also, two Revolvers on a single point don't really work well, so you have to extend one or the ropes will drag. For these reasons I've stopped using Ropemans as it's easier and lighter to do this on a prussik