Maris, spot on, the slightly longer focal length does appear to suit my photographic style, as well as wide angle lenses more than occasionally. My least used focal length is 150mm, followed by 65mm. This year, I have probably used the 250mm and 90mm lengths equally. I carry 65/90/150/250 with me, this range of focal lengths is perfect for how I see and work.
I also have a Komura 400T, which is excellent, but....
Yes, it is the legendary 250mm lens that covers 8x10" format; no, it is not mine.
I was at a friends property and my friend of 45 years or thereabouts turned up with his outfit, which I was going to photograph. A neighbour walked in and saw me using the 4x5" Shen Hao, he saw me switch from the 150 to the 250 and heard me say that this is the best lens I have; meaning for my 4x5" work it works well for me. He walked closer and mentioned that the lens I was using was alright, but he had a better one, would I like to see it.
He popped back to his property through the back paddock and returned on a quad bike with his kit; 8x10" Toyo monorail with three lenses, 420, 300 and the 250. He also has a 5x7" rear end and is interested in getting a 4x5" rear end for the Toyo, but that's another story. As he was running his lenses on a Linhof style board and using a step up board for the Toyo, I was able to try the 250 f/6.7; nice. All three of his lenses ran 67mm filters, with the longer focal length lenses being L Fujinon units, they were quite small, as in, really small. Seems he used to do product photography in another life, hence large coverage lenses.
I don't really think there is much between them optically, other than the legendary coverage of the f/6.7. Would I purchase one, I doubt it.
I wondered whether anyone would pick up on the lens.