This particular pen is a one-way street for small fonts and anything closer to calligraphy with a ballpoint.
It is wonderful, lasts a long time, I have been using it for years in black and blue, and only had 2-3 pieces present a problem after a while (most of them write again if the tip is carefully passed through a small flame).
I put it so-so in comfort, just because after the experience of the fountain pen, every ballpoint pen seems to strain the hand more because it requires more pressure.
Prefer this one in Extra Fine, but also in Fine.

It is my favorite. Very convenient in hand and comfortable in writing, and I make much nicer letters effortlessly when I use it. And the ink is filled up to the top.