Since I am a newbe in the 707, I have not flown on the INS yet but have loaded lat/longs to it and played with the controls to verify it works correctly. I have had the CIVA INS installed in an AFG Beach 300 for a while and I use it regularly since it will allow me to fly a track out and back to the same airport, I use VOR1 to calibrate. It is set up as a single CIVA and works just fine. I will admit that I must use the manual every time to set up the updating as any variation from the procedure will cause it to malfunction. The programming was definitely created for someone who loves to follow process sheets  :)

Dave