The manual shows the rear facing camera covering the interior, is this suitable for mounting on the internal side of the rear window and monitoring external traffic?
The second camera when mounted on the inside of the windscreen will provide more internal coverage than external due to rear window tinting and obstructions through the vehicle. Mounting the second camera inside the rear window directed backwards is the best approach.
Given the video signal supplied to the Visiondrive main unit is NTSC, any camera providing a signal in that format can be used and we are trialling some alternate reverse camera packages right now. They do require their own 12 VDC supply though as the output supply from the Visiondrive recorder is 5 VDC.