The Zebra brush pen is one of my favorites, hands down. When you begin using this brush pen, it behaves rigidly and with little give on the downstrokes. Work with it for a bit, and I mean really push down on that tip during the downstroke and it will break in to the point where you can push it to a 90 degree angle and it will spring back. It will retain a permanant kink in the tip, but it will continue to perform for you. Keep pushing this pen to the limit and it will develop a blob of felt tip marker ink on the end. No problem. I trim that off with my x-acto knife and keep going. I've run these dry and still been happy with a dry brushstroke effect. You know the life of this pen is over when the tip begins to separate from the shaft of the pen and splays out slightly. For $2.50, I trash one of these every two weeks.
I don't mention it in my lefty supplies list for a couple reasons.
1. BAD HABITS
I developed some bad brush-lettering habits with it. When you're using a brush marker that creates an inconsistently sized downstroke, your overall character x-height can vary... a lot! When you're beginning a practice, consistency is key. Using the same pen to produce a character with a 5-15 mm x-height is not very consistent. My other odd habit with it is to push straight down into a downstroke. You cannot do this with many brush pens and it's kind of cheating. The idea of the downstroke having a nice thick shade has to do with using the side of it as you pull downward. Not smooshing the tip into the paper until it bends to your will. Bad habit!