While fountain pens are nicer to write with, they are also more demanding than ballpoints (humidity, temperature, paper quality, writing surface, blotting etc.)

While fountain pens are nicer to write with, they are also more demanding than ballpoints (humidity, temperature, paper quality, writing surface, blotting etc.). Hence, for reliably being able to take notes it might be a better idea to carry a space pen (pressurized ball point) instead of a fountain pen. However, if you can control conditions and for example write comfortably at your desk, a nice fountain pen is preferable.