Leif,
I am not at all up on scanners, but as the mention was of the Nikon unit used, being the next best to drum scanning ( which I assume is the best ) I am a bit puzzled as it is not obvious to me that this is an unfair comparison.
You mention scanning using a macro lens and tubes, so assume you mean taking a pic of it a la slide copying. If so is a camera sensor superior to a scanner. Sorry I am a bit lost here.
Don