I use this product every day. I have tried every navy blue liner there is (practically) and this one is one of the best. Took me a minute to figure out how to advance the product out of the inside, but it is neat because it stays sharp. I will say I feel like it doesn't take long to go through one of these, but I use every day and line my upper and waterline (have forever and ever). I also will layer a thin line of black marker liner over it. Sometimes it does run a bit by the end of the day if its hot out. Love the color though and that it sharpens itself. Will continue to buy.