Water-based writing is smoother, and the words written have a sense of frustration and rank dispersion, which is more beautiful. It can be used to practice calligraphy or participate in competitions, and there are also special ones. Neutral ones are easier to decide and the strokes are not obvious.
There is always its own length, water-based is not easy to write on cloud paper, and neutral is ok.
There is also a pure oil, which is not easy to wipe off when written on clothes and hands, and it is difficult to wash off even if it is washed. It is usually used to write advertisements and put them on the outside, which is more expensive. Hehe, I've said a lot, and I don't know if it's useful to you.