It's an interesting project. It doesn't have the slew rate of the brushless DC gimbals, but it's got the torque of a large heavy-duty metal geared servo. So if your suspension doesn't need the speed of a brushless gimbal or you don't want to have to deal with temperature dependencies and servo tuning, this may be a good alternative.
Some things that differentiate it from the GS-1:
It's continuous rotation, and can either be used in a way that drives to a particular location (traditional servo mode) or it can be used in pan mode (similar to a continuous-rotation pan servo for a KAP rig.) Apparently this is set up in software, so no hardware mods necessary.
It comes out of the box being able to rotate 360. So using one for the tilt axis of a KAP rig should let you tilt from horizon to horizon with zenith and nadir included. I know not everyone wants that, but it's kinda nice for vertical panos.
I've got a question in to the designer about maximum axial load and whether one can be used in the pan axis. (I want to see if I can safely move away from gearsets on the pan axis on my rig.)
You can power it directly from a 2S LiPo battery. I know this isn't of interest to everyone, but for people who are running LiPo batteries on their rigs, there's some attraction since it means there's no need for a voltage regulator. (But keep in mind that the cables and peanuts from James Gentles NEED to run below 6V or they burn! So careful running higher voltages on your rigs!)
Anyway, figured I'd share. The things look expensive, but for DSLR-sized rigs they may be cheaper than a comparable brushless gimbal so long as your suspension can take out all the high frequency / high angular velocity jitter.