Careful now.
Len is a gent in every way, but...
Len is not an appraiser much less a "smith" anymore than the 300 is a "standard".
A rifle such as the 100 is many times more rare than the FWB 300. They are not really in the same availability class. You will find 3x the amount of 300s to 100s. Kind of apples to oranges really.
Anyway ,the 300 is very nice, but the 100 is world class. There, that is my opinion and im sure Len would agree.
It can easily be argued that the Diana 75 is more a FWB 300 equal, but that would be silly, as the OP asked for a value on an ultra rare D100 and not an opinion on a mass produced target rifle.
Just sayin'.
I don't check in on this forum very often, but on those occasions when I do, I certainly don't appreciate seeing statements such as those highlighted in the above quote.
What do you base your opinion of my qualifications on? We have never had any dealings or communications.
I have done appraisals on entire collections, and been involved in the disposal of a few collections involving dozens of airguns.
I have been repairing airguns for over 45 years now, and have worked on everything from the simplest of break barrels to state-of-the-art match and FT rifles, and dating from the early 1800s to current day.
A couple samples of my airgunsmithing capabilities can be seen here:
One of the first D-100s that I repaired, and cross referenced replacement seals with readily available ones:
http://www.network54.com/Forum/405945/thread/1352759919
I built a working reproduction of a very rare airgun, from 1910 patent drawings, and a few blocks of steel:
http://www.network54.com/Forum/405945/thread/1436458713/1/Building+a+Replica+Webley-Whiting+Air+Pistol
And last but not least, no, I do not agree with your opinion of the D-100.
Grauhanen has the facts straight.
The D-100 is no more special than any other 10M match rifle. It is indeed more rare than the FWB 300, but sometimes there is a reason for that rarity, and in the case of the D-100, it was bad timing of it's release to the 10M shooting community.
All of these vintage 10M match rifles were world class, and still are.