The principle is different. If you used a better x-ray to search a randomed bag after it went through the first x-ray you would have a similar case.

Notice the Court made note that the method of detection was the same, metal detection, and it relied on the same information, the presence of metal. It also said it could not "sustain a subsequent search that differs in material respects from the search initially approved".

I think that a hand search would be different in material respects than an x-ray.

Remember as part of the argument is the "current technology" bit. Are you claiming that a hand search is "current technology"?