One negative behavior that I've noticed with this ink is that it does not work well with highly-absorbent papers. It's a fairly wet ink, so uncoated papers tend to drink the ink very quickly, which pulls more ink out of the feed as you write. In most cases, it isn't a big deal — especially if you're writing on coated paper (like Rhodia). But for cheaper paper or uncoated paper, it can be disastrous. In my testing, Baron Fig paper performed the worst. I like testing Baron Fig because it's so unique when compared to the other paper brands I keep on hand. It's thick, but it's also very absorbent and tends to bleed and feather very easily. In the case of Kala Dude, it not only feathers and bleeds, but it also pulls ink from the feed so fast that it causes my pens to drip large dots of ink while writing with this ink. That's an impressive but inconvenient example of capillary action! So, all that to say, don't use this ink with uncoated, absorbent papers.
Kala Dude is an ink from a brand that I'd never heard of prior to trying the ink. I'm happy to say that I'm really pleased with this ink and look forward to trying other inks from the Taiwanese brand. I'm also tempted to try out the other seven crazy colors!
(The Pen Addict purchased this ink from Shigure Inks at full retail price.)