In reply to Xharlie:
> "It comes complete with a screwgate karabiner which is designed to be used with the device, and the device should always be used with this karabiner."
> Show stopper! Why must the manufacturer supplied 'biner always be used? Is it unsafe with any other, ordinary, rated screw-gate?
> I consider the omission of a drop-test to be a flaw in this review. I have seen what a gri-gri can do to a rope (and its sheath) when shock loaded. What will this device do?
> What about ascending? A gri-gri (or Reverso, in fact, if your ropes are skinny enough) can be paired with a prussic (for trad. climbers) or a single jumar (for those who carry them) to make a moderately efficient ascension system - probably only beaten by a proper double-jumar setup. How does this compare?
> Who are "Climbing Technology"? What's their 'street cred'? What else have they made?
There were problems using other karabiners, specifically that they would prevent the Up locking or braking at all and for good reason they supply them as a set. With some other HMS karabiners it works but you need to be sure it doesn´t rotate hence the clip on the CT one. Something like a DMM belay master for example will prevent the Up working. The Alpine Smart is the same but all of this type of device are more or less karabiner sensitive, personally I also find this is a downside but it´s fairly unavoidable when the karabiner is part of the braking mechanism, the TRE Sirius avoided this which is one of it´s plus points.
I´ve never seen any interesting damage to the rope with a GriGri 1 and I´ve overloaded one hundreds of times, even to the extent that the whole thing bent and finally the rope broke elsewhere when I put a stopper knot in to stop the slip which normally occurs. I use a GriGri to hold the rope on one of my pull testers and they have also been used as a rope retainer with a stopper knot in one of the most extensive tests ever done drop-testing belay devices to destruction, it survived no problem.
CT are an offshoot from another extremely well known company and have an excellent reputation amongst those who know the climbing hardware industry.