I was intrigued by that as well OP, so I started an experiment : take each of the 'default' ships out to the Nav Beacon and leave it, count the scans, see how they differ.
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Next to the problem of different instances having different seeds and thus a different density of police, I also wonder if you differ between scans at all. The Krait is not supposed to be less likely to be scanned by criminals or bounty hunters. The only thing which should happen less frequenty is cargo scans from system security. And even there, if I understood that right, it's not like they refuse to scan the Krait, only reduce the priority of doing so.
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All in all, it means the Krait should have a bit longer time window before getting scanned when flying towards a station. How to properly test this, that's the real question. And due to the number of variables around, I fear that no single person is able to come to a reasonably accurate result in any reasonable time. The only concept I'd come up with would be automated. It would require a number of bots doing the same "leave to supercruise, return, take the time till you are scannen, repeat" cycle in many different ships. But as this would be a bannable offense, I think the price outweights the gain.
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All we can do is collecting impressions of many players and see how things turn out in the long run.
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