I bought my 2018 Jazz secondhand, and it came with a Blackvue DR750S-2CH dashcam fitted to front and rear. I have never had a car with a dashcam before, so I have no experience of what is good, bad or average.
I find mine gives good video images - numberplates on cars are clearly readable. It seems to record in units of about 1 minute and save them to an SD card. When the card is full it starts to overwrite earlier data - but the SD card is 64GB and holds a lot of data.
Extracting video from the dashcam can be a bit of a pain - The SD card is stored in the front dashcam - you have to bluetooth a mobile phone to it, scroll through the saved data, decide which bits you want to copy to the smartphone and then you can, if necessary, transfer from the smartphone to a PC. Alternatively, although it is a bit of a fiddle, the SD card can be removed and slotted into a PC which makes it much easier to analyis the images on a PC screen rather than on a small smartphone screen.
When I first got it, I did not realise that these dashcams can also record sound, so the first time I played it back as well as the view ahead and behind, I got myself and Mrs FarNorthJazz conversing. It was fairly easy to switch the sound recording off to save any future embarassment !