I tend to really rely on Copic Multiliners to get my inking done, since I know they're Copic-safe. Lately, I've become bored by how limited I am with Multiliners, and have been branching out, testing new inks with Copics. This is Pilot G-Tec in a size .4, and to build up lineweight, I sketch the line several times. This allows for an open, airy inkjob that works well with the lightness of Copics, without feeling to coloring-book. This type of inking is more fun than slavishly using tech pens, and moves a lot faster. The gel ink in the G-Tec is also surprisingly Copic safe, especially if you let it dry overnight.