I can’t help myself. I did try putting a Z50-M nib on the Wing-Fari. It fits, it writes, but there are problems with the nib, as soon as it is on the pen.

It writes very much like a B nib, scratches heavily on the upstroke when I hold it normally and there is a visible misalignment between the tines, when I look at the nib from the side. The nib is fine when pulling it off the feed, fine as well when put on another pen. Something in the feed isn’t perfectly fitting the LAMY Z-series nib shape. Forgive me, for not providing a shot of the misalignment, but my camera microscope is nowhere to be found. I ordered replacements, maybe they will arrive in time to update this post. Stay tuned. It was delivered today

The pictures explain clearly, why the nib is ‘scratchy’ on the up stroke. Mechanically, the nib fits though. It sits tight enough to not fall off but not so tight that is terribly deformed. It might work on another pen with another nib. I am giving up on this.

My final verdict remains: This pen is not fit for use without this mod, it isn’t any better with it. I’d stick with the originals.