On plotting chart, there is a section which, for every 10 degrees east-west of passage, you can plug in the north or south coordinates (ie, 54N to 52N), and get a distance and initial course. This allows for checking accuracy of programmed waypoints; gross errors become obvious (I've found some potential gross errors this way, due to finger blips, and one actual data base mistake). This course data uses True; thus, to access this info, True info must be used (changeable mag variation is thus not a factor). Also, True course plots are much easier to see on the chart. My company, upon entering Oceanic Areas, changes to True, as policy...a good one, in my opinion. As for fleet, I was 747 classic & 400, just graduated to Falcon 900, and use this aid regardless of fleet.