Unfortunately, in that preview, the (interlaced) GoPro footage has been incorrectly processed. If you pause the video at any point, you'll see the double-imaging in the GoPro footage - an immediate sign of incorrect processing that isn't the fault of the videocamera.

This happened because the GoPro probably records interlaced footage, which didn't get properly deinterlaced by the video-creator's software. Basically, the GoPro didn't get a fair trial.

That said, the SJ4000 footage has a decent quality, and I'm all for capable competition.