Writing with a Space Pen is exactly like writing with a medium point ballpoint pen.

There is a rumor that some German company makes a refill for the Fisher space pen that makes it more like a fine point (or even ultrafine?) ballpoint, which would be a little nicer (just as long as it doesn't slice up your paper)...

So overall it's a disappointing feeling writing with a fairly wide ballpoint; however, it writes upside down and is shorter than the length of a typical men's wallet. The writing upside down is really nice if you need to stop somewhere and prop a piece of paper up against a wall and write on it.