Pete,
This is a subject in which I find some interest.
Condition grading of guns is not a science, nor perhaps even an art, it comes closer to voodoo or the casting of bones. I tried to start up a discussion a while back on the topic
(percent finish topic link), there seems to be little consensus about methodology or result, or perhaps even the usefulness of percentage grading.
But since you have provided some pictures and your own comments, lets pursue them a bit.
It is very difficult to photograph a gun so that the picture accurately portrays the characterisitics of wear and finish which we want to use to grade the gun. Lighting, contrast, and exposure all conspire to make guns look better (usually, in my own photographic experience) or worse (occasionally) than they really are. Thus, assessing condition from a photograph is already a step removed from reality.
A photograph may not show everything necessary to judge the original assessor's conclusion. In fact, the dealer's website for the samples you selected have a second photo, of the opposite side, of both guns. Seeing these pictures would give people additional information to assess the assessment. What neither set of photos shows are other areas which might be revealing for a percentage assessment--for instance, it appears that there may be no wear on the grip straps of the Astra, which would raise an assessment of its finish percentage considerably.
For additional discussion, this is a link to photographs of a
1900 American Eagle purchased recently from this dealer, stated in his brochure as "Fine, 97%".
--Dwight