Kuretake Zig Letter Pen CocoIro Pen Refill - Super Fine - Dark Green

Of all the ink colors in this line, black is the smoothest I've used!
It does take some getting used to, but the tricks this pen can do are cool! Writes variable line widths, no skipping, smooth flowy ink, even when you write fast. Its not scratchy to me, and I am very picky about scratchiness (Hi-Tec C 0.25 mm, I'm looking at you!).
Writiing in English or Japanese (I can't write in any other languages but I'm sure it handles just the same) looks very pretty and you can even get a lttle fancy with your script uusing the Letter Pens, without even trying too hard.

Yes, you can use these refills alone without the pen body, but I suggest you get at least one pen body to try oout. I pprefer using the pen body not just the refill alone.
(aand, sorry for the typos, I'mtyping on my phone!)

Bought this pen to practice chinese calligraphy, and I'm pretty disappointed. The pen writes very wet, causing the ink to feather and bleed on cheaper paper, or take a small eternity to dry on higher quality paper. The brush part is made of synthetic fiber and holds its shape surprisingly while still giving lots of nice variation. Unfortunately, it's also super thin and really really hard to control. I'll probably end up buying on the normal fine/extra fine refills next time.

This is a nice burgundy color, but it's a little too transparent to pass as real blood -- it's got a sort of watercolor quality to it. It's very close to the Marvy Uchida burgundy, but a little more transparent. It's roughly the same deep red with a hint of purple as partly-dry blood (not as red as freshly-spilled blood, not as brown as old dried blood) but not as opaque as real blood. (If that's your thing, you might want to try using an opaque acrylic paint instead.)

The Zig pens have a bit of a brush quality to them (with a small, mostly-stiff point) that gives a line quality similar to a Tradio/Pulaman/Fountain Pentel, but the Zig has many more color options. The Tradio/Pulaman/Fountain Pentels go "scratchity scratchity scratchity" when you write -- and sometimes "spit" little droplets in a random direction. The Zig writes more quietly, and has similar thicks and thins, but without the occasional spitty surprise. I personally prefer writing with the Tradio/Pulaman/Fountain Pentels, because their scratchiness grips the paper firmly and their ink is a bit darker, but I suspect most people will prefer the Zig's predictability and wider range of colors.

These are definitely my new favorite pens! Simple, sleek and inexpensive. I started with brown and have just gotten blue black and black. They write smooth and even better I love drawing with them. I actually use them in combination with copics and they don't smear. I haven't had any problems with blotches or dryness and for the amount of use they've been getting they still haven't run dry. The pen bodies are cute and feel comfortable to write with. Also, I definitely feel like they're better made than the Tradio Pentel pen body, which its plastic grip feels cheep. The only problem I've had so far is when I first got the black refill it needed a little dab of water to start running. Other than that an overall great pen!

Very smooth black lines. Definitely does NOT write like a 0.3mm. Closer to 0.7mm maybe. Just FYI in case you were thinking this would give you a fine line.