Iroshizuku have been my main ink brand since I got my first bottle of it. These days I'm mostly exclusive to them.
For the longest time I was a only black person, then I got into colors, bought a bunch of ink and used five years to get rid of it all.
Now. This was the first ink I bought after that.
It is a great dark blue. And I love it a lot. Based on how much ink I have used from this bottle compared to all the others I got at the same time it is the one I like the most. It is a really good blue.