I'm fixing to install my VanTrue N4 (forward, cabin, & rear), soon. I just need to tear my cab up just a little bit to route everything. The only hard part, that I see, is getting into the fuse box and the headliner.
I threw our Uniden "Witness" ($60) into our son's (use to be daughter's) Civic, took 10 minutes to route the USB cable to the DC outlet. The only downside is that every 45-60 seconds it saves the last 45-60 seconds of video to the card and misses about 0.5-1.0 seconds each time. BUT, this was our "use everywhere we go" dash cam. Shortly after getting this vehicle (April 2021), my daughter got sideswiped getting onto the highway and changing lanes to pass the SLOW truck that got onto the highway in front of her. B!TCH stopped, tried blaming my daughter, and left the scene (when her friend/co-pilot noticed that they left paint transfer on our Civic). Even CHP speculated that they were doing 100 coming out of the construction zone (single lane, both directions, 55, NO PASSING, for 10 miles), and that's why my daughter never saw them until they collided. (Beside the point: It also happened on my daughter's first day on the job at BJ's, and the manager(s) were impressed, she didn't act like she was in an accident, and it was her 21st birthday weekend.)
HINT: Whether or not if you have a dashcam, take photos of the other vehicle(s) and driver(s), when you're in an accident (even if you're at fault) OR if you witness one (they may be shaken up enough to not think about it).