The POSCA paint pens are my ultimate favorites. They are very high quality. There are 7 tips available so you can get an assortment from ultra fine to bold. The nibs really feel great - AND they pull out and can be rinsed clear in water or reversed. The bullet shaped tips are great, as the tips narrow down so you can make a fine line. The white is truly opaque and I am THRILLED with these pens. I got extra-fine, fine, and medium. They have a beautiful flow. My friend Molly told me about them and I'm glad she did!
We ordered ours from Durable Supply Company which offers them at a good discount:
Posca Paint Markers
For the little pens, I have tried them all and my favorite is the Sakura Gelly Roll. But I love the beautiful flow of the POSCA pens a lot more.
I have several Uni-Signo pens that have plenty of ink but they won't write. It is like the tips are dried up. Someone mentioned tips to get them going again, how do you do that? Also, I store them horizontally, is that a problem? I go to throw them away but then I get aggravated because they should write, they have barely been used.
The Ranger pens always started skipping on me, I would have to go over a line several times on dark card stock.
I got the fine tip Sharpie white paint pen and after two uses the whole tip assembly cracked and pushed in when I gently depressed the tip to start the paint flow. Ruined my project - I was on a scratch piece but it was next to my project and paint flowed everywhere!