Once upon a time, they used to change the mount on those lenses so that you didn't need an adapter, but I haven't seen these is several years. They also reversed the diaphram and put the metering pin holder on the ring so that it worked just like a Mamiya manual focus lens. Wish I had bought one of those when they were still around.
I have one of the Zodiak 30mm and it is OK, a little too much CA on the edges near wide open, but not too bad considering the price.