Eyedropper filling a fountain pen is useful for ink capacity, and downright fun. You don’t HAVE to eyedropper the Pocket 20 pen - it takes short international cartridges - but I think you are missing out by not doing so. Look at the ink sloshing around the barrel! And yes, it is as easy to clean as any other pen.
The Pocket 20 is useful because of its size. It fits anywhere, and goes everywhere. That’s why I love small fountain pens so much. Toss them in a pocket and go. I primarily use this model unposted, but the slip cap posts securely on the back of the pen for a full-sized writing experience. I opted for the clip on this model, since I normally go clipless, to mix it up a bit. Plus, I preferred the aesthetic.