For the most part this tree is world class because it's a legacy tree with a long and famous history. I remember this tree from Yoshimura's book in 1957.
This one is in Yoshimura's book:
Looks like it's in a shallower pot. I think it might be the same one as in the 1939 picture, but the front had been switched for this picture. I'd guess that this was intended to be the back of the tree when it was potted - look at the defect on the right side of the pot. That wasn't visible from the other front in the 1939 picture. I think that's interesting - according to the BT article, the front wasn't switched until it was restyled in 1975, 18 years after Yuji's book. I wonder why the owner allowed the back of the tree to be photographed? Were they thinking about switching the front? Did they switch fronts from time to time? The other thing I noticed about it was that in Kimura's care he planted it a lot deeper, burying much of the nebari exposed in the YY picture. Interesting - I wonder why he did that? The nebari is nice, I think.
One of the things that makes this juniper famous was that it was collected from Mt. Ishizuchi on Shikoku Island in the 1920's and planted as a garden centerpiece for almost a decade. Mt. Ishizuchi is a very famous collecting area and many other fine bonsai came from this mountain. So it had good provenance. When it was sold for the first time as a bonsai in 1938 it commanded one of the highest price paid for a bonsai. It was shown in Kokufu 29, 37, and 43. When the Nippon Bonsai Associate created the Register of Bonsai Masterpieces in 1980, this tree was one of the first entered. It won the Dai-Ken-Ten in 1981. But I've not found any reference to it since the 1995 BT article. I wonder where it is now?
I love those early Bonsai Today magazines. I still go back to them all the time.
Scott