Reading the inspire forum it was very interesting to see guys talking about getting a good calibration and to stick with it rather than perform one every flight, reason for this is that there might be some external factors that will influence the calibration and now you stuck with those values till the next calibration, I personally do not perform compass calibration every flight but do check my values pre flight! Seems the general consensus is that 1500 is the sweet spot, how do you guys see this? I have had 14 flights since my last compass calibration with no issues at all. I will calibrate if I fly in an area far away but around my town I don't see the need if I have a good calibration and my values look good. What do you guys think?