Lets hope the did as good on the DV688 as with the B1W.
Unfortunately this isn't part of the B1W family, it is one they are reselling like they resell the mini 0906, so don't expect B1W quality.
The two little remote cameras are nice, a nice size and easy to mount and connect up. They have a nice FOV for a bike, narrower than a car dashcam because bikes are narrower than cars, so they see more in the distance than a car dashcam does.
The mounts are almost GoPro mount compatible so you can mount them almost anywhere.
The clamp is a little loose in the GoPro tripod adaptors I used, but that can be sorted.
Not sure they are immersion proof, the cable connectors don't look 100% waterproof, but they do seem rainproof and are easy to install.
Maybe a little Vaseline to keep the moisture out would be a good idea in damp environments.
The main unit is OK, but the Allwinner V3 isn't a great processor, reminds me of a cheap action camera, the sort I would be happy to give to the kids.
It only records 720 levels of detail even though it is true 1080, no interpolation but no texture to surfaces. However, because the field of view is narrower than a car dashcam number plates are recorded OK. Seems a bit expensive for the quality it gives, but it does work and there isn't much competition for waterproof dual remote cameras.
Both bitrate and frame rate are quite low:
Format AVC (H264)
Bit rate 7336 Kbps
Width 1920 pixels
Height 1080 pixels
Display aspect ratio 16:9
Frame rate 26.220 fps
The GPS also seems to be a cheap one, takes a while to lock on and then the map trace wanders off the road, but again it does work.
Sound quality is OK as long as there is no wind, but of course that is a problem on a bike! No external microphone connections, although the microphone is in the wired remote control so is effectively an external microphone, if you can place it out of the wind then it is OK.
No super capacitors, it uses a lipo battery for shutdown, but it is replaceable without disassembling the unit. It is a bit power hungry, using 0.95 amps average from my USB powerbank, compared to 0.15 amps for the B1W! But it does come with a hardwire kit so on a motorcycle that wont be a problem, and you should have plenty of cooling so that it doesn't overheat, maybe not wise for an enclosed vehicle though.
The other issue is that it is not easy to unplug since there are multiple water resistant connectors to undo, which means that you will be leaving it on the bike, which for some people might be a security problem.
If you want to make movies on your bike then use a decent action camera with stabilisation.
If you want a rainproof accident camera for your bike then this works OK and the little cameras look good, but it can't easily be removed from the bike to avoid theft.
A waterproof B1W would be nice, but this isn't it, it is not part of the family, not the same quality, and since it is not manufactured by Blueskysea I guess it wont get the same level of support either.