Doesn't live up to hype.
I tried the aqua flow pens, thinking it would be easier than watercolor pencils & a water brush, but it didn't work out well First off, it was hard to screw the ink portion back onto the barrel of the pen correctly. Second, it was hyped as having a pointed tip for detail work, or a brush for broad strokes, but I had to press down so hard to get the ink flowing that the fine tip was destroyed & I was left with only the brush for broad strokes, which made it next to impossible to control where I placed each color in the project I was working on. Finally, the ink bled too much so I ended up with a blobby, blurry mess.
Prima's watercolor pencils & aqua brushes were much better, & I'll be sticking with them in the future.