We R Makers Pigment Oens
Love the colors but cannot make very thin lines. They also leave little pieces behind which can make a mess. There is definitely a learning curve to using these well. If I can master the use of these pens I will buy more, but not until. I agree that it is hard to stay in the lines and that a tutorial on how to use them would be very useful. Like the twist up feature and colors are fantastic. I recommend these because of the beautiful colors, but have some hesitation as described above.