Here is my rear facing camera with a circular polarising filter to help and reduce reflections. ( Model: Roadhawk HD)
View from inside cabin
Front facing camera
View within the cabin from front passenger side, The camera is totally hidden from the driver position as its hidden by the rear view mirror. ( Model:Blackvue DR500 GW)
The benefit of the Roadhawk HD as compared with the Blackvue DR500 GW is its lower profile is being only 25 mm in height and 95mm long. The Blackvue DR500 GW is 36 mm dia and longer being 119 mm. So it is not distracting in the rear view mirror. I choose not to go for a 2 channel approach due to the poor quality of the video output (low bit rate).
A recommeded website forum for dash cams is
http://forum.dashcamtalk.com/
I got the local dealer to install the cams they did an excellent job, even exceeded my expectations, they also installed the PowerMagic Pro adaptor to provide me with park mode capability.