We decided to upgrade our A119 V3 to a two channel system and chose the A229 Pro from BBMC based on the stellar service and support we had from them on our 2 previous dash cams.
I was concerned that with a 4K system, elimination of vibrations was crucial so I did not use the static film. Instead I mount the A29 Pro directly to the windscreen. It is slightly off horizontal but not enough to worry about. The cables are thin enough to make out easy to slip under interior trim panels.
I am delighted with the video quality. Number plates and street signs are clear and sharp. The voice controls respond quickly to my voice despite my accent. The wifi connects to the app quickly and while the app UI is a bit clunky, I find it easier to change settings through the app than on the Dashcam itself.
At the highest bit rate and resolution the two channels produce a combined file size of around 2Gb for 3 minute videos so I estimate that a 256 GB card will give around 6.4 hrs of recording.
Due to rather gloomy weather, I have yet to try HDR.