This pen is incredibly hardy. I have a bad history of screwing up fancy pens, so I like refilling disposables. They take a lot of hard knocks and come out unfazed.
This pen comes with rich black ink, and you can refill it with whatever you prefer by simply grasping the nib assembly with pliers (gently but firmly) and removing it. Rinse, drop the ink into the barrel, replace nib, and you're done!