I tried one of these, and plan to buy a few, but only in colors that I can not get in pencil or fluidline form. They DO stay put, and the colors are very vibrant, but I feel that I have more control over application with a fluidline. They are not recommended for waterline useage and I have heard that they burn if they get in your eye
Alot of people are having better luck with them if they use a brush other than the one that they come with. I am really new to liquid liners, so maybe as I get more used to them I will love them, but I prefer fluidlines and pencils. The best thing about them is their staying power, and their bold, bright colors - perfect for spring and summer!