The list of pens that I've owned for over a decade is extremely small, but the Fisher Space Pen Bullet is one of them. At some point in high school, I picked up a matte black version of the Bullet with a medium point. I only recently replaced that refill with a fine point, which I prefer. For me, this pen is all about the aesthetic and form factor over the writing quality.
People have different opinions about the writing characteristics of the Fisher refills. I find them extremely useful and utilitarian, but they aren't particularly enjoyable to write with. That's not a problem with the Bullet, however. This pen is my go-anywhere-anytime-no-matter-the-risk pen. If it's not bullet-proof, it's pretty darn close. It's never failed me in its many years of use.
The line that the Fisher refill is like any normal ballpoint refill. It's smooth and easy, but the line is a bit varied and sometimes skips a little. I've had better experiences with the fine refill over the medium. This isn't a major concern for me since I usually carry this pen as a tool instead of a writing instrument that I enjoy using. Different tools for different jobs, right?
This was a favorite pen of mine before I became a Registered Pen Addict (RPA). Of the dozens of pens I own now, I think it might be the one that holds the most sentimental value -- I mean, look at all the character on this pen! If I bought a new one, it would never be the same pen. This pen has a history that can't be repeated.
The Bullet is a solid pen that I really encourage you to try if you haven't. I personally like the clip, though some might worry about the security risk it poses since it is removable. In normal use, it's quite strong. It also serves as a sleek anti-rolling device, too. Personally, I think black is the right color, but there's plenty of other colors to choose from.