I think there is a lot of misunderstanding about Kenko Tokina. They are in fact one company. Also their main business is not really their own lenses, but being the Japan distributor for a number of more popular overseas brands. For example, they distribute Zeiss, Samyang and Less Baby in Japan. They also sell Tamrac, Aosta, Skin, Meade telescopes and a number of other brands in Japan. They also seem to have other interests in making goods for people with disabilities and some other random stuff.
Their head office is quite near to where I live. It's a kind of shabby building, but I have a soft spot for it because the showroom/shop is a kind of messy curiosity shop of optical related items. When you go in they have a small Horseman museum. There is a display of the Tokina designs from the past (they haven't made that many lenses when you think about it). Then there quite a bot photo studio area, which Ricoh Imaging sometimes rents out for events. They usually have a display of photography, but it's not a nice gallery. The main part is just rows of filters, reflectors, lenses, microscopes and other stuff.
Kenko also make their own compact cameras, which are not very special or good. But I do remember they made a fixed-lens fisheye compact a few years ago, which I was tempted to pick up just for the novelty value.
You can see the products they sell by category here.
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And here is the page that shows some images of their showroom in Nakano, Tokyo.
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So given the modest scale of this company, it always seems silly to me to hear commenters claim that Ricoh relies on them for lens design. It's totally the other way round. They are mostly in the business of distributing and rebranding the lenses of others, including Pentax on occasion. Despite that, I think they are a cool little company.
I notice that some commenters on DPR are complaining of the doughnut bokeh on mirror lenses. It's a distinctive look, but at least it is consistent and looks intentional. The nasty tendency for mirrorless lenses to transition to cats-eye bokeh at the edge of the frame is much more obnoxious in my opinion. That seems to be a compromise to make the lenses smaller that everyone seems to be OK with, but I personally think it looks like a defect and the doughnut bokeh of mirror lenses is comparatively benign.