Hi Massdrop - I am writing this out of concern in how you market this paper to users.
As a primarily a fountain pen user - I use nibs ranging from EF - M as my "go-to's". When I received the books, I immediately tested the paper.
Using a Pilot Metropolitan in fine nib- with pilot blue (an ink which behaves well in multiple papers/nibs) I have horrible spread with the ink. It also has quite the shadowing on the back. You can clearly see what was written on the reverse side.
I also tested with a different ink and pen (Stipula Passporto Fine with Iroshizuko Asa Gao ink) and had similar results. The spreading caused the lines to look like a medium nib.
I am quite disappointed in this paper as how it was advertised, using an Italic nib showing little spread with the fountain pen. I can see from the photos that the permanent marker and brush pen feathered and spread, but using small nib sizes and well behaved inks should not cause this.
Additionally, other commentators showed little bleed through with their own nibs/inks onto the back.
Can someone please contact me?