According to Wikipedia, a gel pen uses ink in which pigment is suspended in a water-based gel. I started collecting them in high school because I always find a couple of empty barrels of Dong-A My Gel 0.5 mm in my bag so I put them in the box of my first ever prescription glasses.
All in all I have 71 barrels. 52 of which are the Dong-A My Gel brand since I used it from 1st to 4th year high school. I like the thickness of the ink especially when it blots on the back of the sheet and I like the fact that less pressure could be put and the writing would still be jet black.
In college, I became fond of writing on yellow pads divided in half lengthwise (notebooks are heavy!). My Gel was too thick that I found myself unable to read what I’ve written on the back page of the paper. Hence, I shifted to Pilot G-tec. I’ve known this brand since high school but only 0.3 mm was available in the province and it was too thin for my taste. Good thing National Bookstore has 0.4. It was more expensive than My Gel but it also lasts longer (unless you drop it without the cap and the ball stick becomes crooked, in that case it’s useless — one major disadvantage). I only have 19 of these because I always lose them and I wrote less in college.
Finally, I have a lone barrel of Pilot Precise V5 Retractable Pen. I resorted to this after I’ve had enough of G-tec’s vulnerability to falls. Besides, I hated capping and recapping pens. Why do that when you could just click right?
I only have one of this because I stopped using gel pens altogether midway between college since they were not encouraged during clinical rotations. They make patients’ charts look dirty and the millimeter line was too thick when you write in really tiny letters(which was inevitable due to lack of space in charts), the words became unreadable.
Nothing has been added in my pointless collection for close to a year now. But who knows, I might start using gel pens again.