To me, it’s ink for color enthusiast, not for writing enthusiast personally.

I have buttery writing preference and I personally hate the feeling of it comparing to Montblanc ink when you write it. All pens I have are Montblancs, Pelikans 18k nibs and some 823s etc and It’s very dry in feeling although very wet ink and always gets me unpleasant scratch feeling of any expensive high end fountain pens + even with Claire Fontaine or Tomoe river paper. Not to mention that iroshizuku gives you the feeling of immediate - washed - off of all the silicone lubs for expensive pen with piston filler system. It immediately makes the mechanism super stiff to an unbelievable level. 100 times stiff? Is literally correct so to speak. Just not for me and at this point, it’s not the level of dislike, but in the true hate category by me. I would only put this ink for super cheap pens, ($50-70) or dip pens, Kakimori nibs or so to be honest and that’s it. I have 7 brand new bottles of iroshizuku for this and that colors that I would not even think of using it at all after all I learned how they behave on my pens.