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I maintain it against a calibrated satellite image which by "tab/alt" I can cross compare.
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You need to be extra careful with these. They do not have that great an accuracy. Before you even get them they have radial distortion that you can't calibrate using any over the counter process. In general it can't be corrected. Using as is is perhaps just as good. Once you attempt to calibrate it, the distortion generally gets worse but "looks" better.
Confirmation from multiple sources clearly is the critical part of navigation many people miss. No information is really perfect. It's nice to have several things telling you what you want to confirm.
I would just be careful when the imagery disagrees. It could send you places you don't want to go. It's one of those errors where you are dead sure you are right and actually dead wrong you end up doubting the good stuff. It basically comes down to when it agrees it is fine but when it does not don't believe it. I just would never doubt a chart over it.