I'm no expert on the dash cam's that are available, but there are plenty of websites that review and compare the kit. I went with the F770 as Thinkware kit gets good reviews, it's sleek and does't have a screen, it's good quality, has a nice features (speed camera alerts) and is 2 channel (front and rear camera's)...it also has a bunch of features I don't use like parked recordings, lane departure warnings, etc.
I see that the Viofo A119S got a good review here; https://dashboardcamerareviews.com/viofo-a119s/ - I though you said you weren't interested in a camera with a screen tho?
In my thread you see that I earthed to the forward fuse board bolt