I don't think there's much difference? The technicians that perform the tests are not doctors. You usually see a doc for 5 mins at the end, to discuss any anomalies. Even then, they're just going to refer you to see your GP or a specialist. At the end of the day, the ningendoku is just information that your doctors can access. I'd much prefer a high-resolution full body scan.

Either way, the patient should make the choice about whether they want that info, not an insurance company or a know-it-all armed with a dubious study concluding that asymptomatic conditions are better left undiscovered.