The requirements for a decent pen aren't extreme, but are certainly higher than just "it lays down ink":
It has to lay down ink when you want it to. It has to be comfortable enough to write with for a while. It has to look good enough that you don't feel shame when you use it in front of people. It has to go with you wherever you go.
So we found three pens that meet those requirements in three different ways.
The Bullet, which is the most delicate and beautiful;
and the Clicker, which is the standard option for day to day use.
All three use Rite in the Rain's pressurized cartridge of high quality ink, which means that the pen can write under water and in extreme temperature conditions. The writing action is a nice smooth ball point feel. It's neither stingy nor overzealous with ink, and gives a good sense of movement as you write.
We sell this one, the Bullet, because of how small it is when stowed. It shrinks down to about the length of a business card, and turns into a full-sized pen when you're ready to use it. It feels sturdy and looks great.
However, this is the most delicate of the three. It would be possible to destroy this pen by putting the cap on the back and putting a lot of pressure on it. Over time it is possible that this kind of careless use could lead to the cap stretching out. But if you treat it well it will last you a very long time.