In reply to NottsRich: On the DMM Belaymaster the safety bar is attached to the spine of the krab and clips to the gate. On the Austria Alpin the safety bar is attached to the gate - presumably some kind of pull-twist gate, like the DMM Locksafe, rather than a screw gate since with the safety clip attached you couldn't work a screw gate - and it clips to the spine of the krab.
It might actually make the Austria Alpin device a tiny bit less of a PITA to use than the Belaymaster...
In reply to Neil Williams: First the confession - I am a gear tart. If it's new and shinny I will buy it.
Compared to the Belay Master, the plastic gate directly operates the gate. It's slightly less of fiddle than the belay master and there a larger gap between the top of the krab and the plastic meaning it doesn't get in the way of the keep wire on bug style devices. In the open position it can still get caught up on a belay or gear loop just like the Master and you wouldn't want to sit or land on it in that position.
Compared to the gridlock, there's less play in the lock so it just feels better made and more like the DMM in that way. I've been using one for a few months now and it's showing no signs of wear unlike the gridlock which developed a noticeable groove fairly quickly. Like the belay master it has the advantage over the gridlock in that it gives a visual assurance that the gate is locked.
I like mine - it's attached to my harness and at the moment I don't feel any urge to switch back to a belay master or gridlock even though I have one of each in the bag. A friend did suggest that the top radius was on the small side should you want to use it with a bug to abseil on a doubled up single from the top of a sport route. To be honest the gate on these devices makes them very much a second choice in this situation but I checked anyway. The radius is fine using a 10.5mm rope.
If you feel the need for this kind of device - and I know a lot of people don't see the point - then its definitely one to consider.