I actually was able to take a look at a friend's actioncam yesterday. Although I do not own a nice rig myself, I have quite a bit of experience with rigs as an AC and as a lurker on the forums.
My take was this:
It looks like it could do the job, but doesn't seem nearly as refined as any of the Steadicam/PRO/MK-V products. for instance, there are no connectors on the top and bottom, merely a huge post to drop wires through...
The arm seemed to be fairly nice, though it bottomed out very hard. action-wise it seemed nice.
the bottom of the sled is based around just 19mm rods and everything slides on there.
I can see it being a fairly nice rig with some modifications, but, if I were to buy new at that price range, I wouldn't even consider it.