The first couple of times I used it I had a hard time controlling the amount of color that went on, and I ended up with crazy painted brows. I used clear brow gel afterwards to thin out the color when I went too heavy. I got the hang of it pretty quickly (light touch and repeat), and now swear by this product for not too over the top brows - Your Brows But Better if you like.
This is my brows using them:
Ooh look, there's still a stray one there, but it definitely cannot be blamed on the brow gel!