This is my first fountain of special nib - Goccia nib. I used to have EF or F nibs for daily use. You may need some writing skill to use it and the line variation comes from different writing angles, not like flex nib by pressure. A very special experience.
I liked to try Goccia nib. So I got this pen. The line variation was very attractive but not very so much. Ink flows well. I think the CE size would be better.