This is the cheapest or better said the most economical / affordable ink on the market, because cheap will make you wonder if this ink is any good, or will it ruin my precious fountain pen etc. The ink works fine and will not clog your pen, but be careful as Koh-I-Noor has in it's offering pigment inks as well.
The ink is addressed to students and comes in a basic plastic bottle of 50 grams. Produced in the Czech Republic, the bottle comes as is, no cardboard box.
But is it worth using this ink if you are not a student anymore? Does it perform well?
The ink performs well on every day paper, without fathering or showing throw the thinner paper, while still having a nice saturated black look. The ink is not very wet and dries rather quickly. Thus, it can be used even with broader nibs on cheap paper. For the testing purpose I used the Faber Castell Loom with Fine nib.
It is a hair wetter than the Pelinkan which dries almost instantly. So if you like the Pelikan but you or your pen would like it to have a bit of wetness, try the Koh I Noor.
My conclusion
If you want an everyday ink, to use on all kinds of paper, it is a perfect contender with its availability (for me at least, it can be bought at every stationery shop), for the good performance it has and of course I can't ignore the great price it is available at. I would go so far to say that it is the best ink you can use as a daily workhorse.
On the other hand, if you are interested in a more refined experience when using your awesome fountain pens, probably you will get more joy using a higher end ink, that comes in a nicer refined glass bottle.