- Traveling and shaking a vessel filled with ink doesn't end well.
- Getting ink on your hands when refilling the pen becomes annoying, quickly.
- Your notebook choices now become limited to ones that don't bleed. I already have notebooks that I've been using for years and don't want to change.
- Not all pens are suited for every language. If you get a pen with a wider nib (like a parker or american ones in general), it's very easy to blur on Chinese/Korean/Japanese etc. This is fixable with a smaller japanese nib but not really an issue with ballpoint pens.
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Whenever I'm in Japan I usually stop by a store like kingdom note and I've picked up some pilor & sailor pens. I'm happy to use them at my desk, but I just stick to ballpoint pens like the Calme 0.7 when out and about.