I really love the applicator on this liner. It's basically a brush, but is very, very thin and firm, so it's super easy to get a precise, thin line and a clean, crisp wing. The Ultra Black color is definitely quite black, and the formula dries pretty quickly once applied.
I don't notice a difference in my lashes, but I only bought mine as an eyeliner, so it's not a drawback for me.
Almost always stays in place perfectly until you take it off.
This is the best eyeliner I have ever used. It's really dark, dries almost instantly, and unless your eyes water or you are crying, etc. it will stay in place perfectly until I take it off. And even if your eyes do water and it does come off, it just mostly disappears instead of smearing all over your eyes and making you look scary. Also, it takes like forever to run out. I just bought my second thing of it today because the first one finally is drying out after having it more than six months. Another thing, I use the thicker version of this. It's the same thing just this is more pen size and the one I have is more marker size.
I am absolutely amazed at this eyeliner. I originally bought it for the brush-type applicator, not the promise of longer lashes. I'd given up on that dream already. However, the stuff inside is what really blew me away, not the tip! I had been using it for a few weeks, liked the color & ease of application/removal. One night while lying in bed with my fiance (after a shower, so I had no makeup on) he asked why I was wearing fake eyelashes to bed. He did not believe that they were my real lashes, he said they've never been so long before. All in all, you really just can't go wrong with this stuff, whether you're looking for longer lashes or a great liquid eyeliner!
compare to eyeko liners
i used to buy eyeko eyeliner (similar felt-tip/marker design) & i LOVED it. perfect size & color. well, they completely "re-did" all of their products including the liners & they came out thinner & more expensive. i bought this to see if i could find a dupe. i'd say it's just as opaque & lasts longer, but the great thing is that there's a mixing ball in the pen that helps continue the flow of product to the tip (the eyeko one dried too easily) i'd say the only downside is the size of the tip. it's too thin for me so it takes longer to build my lines to the thickness i want, but on the other hand, it allows for precise wings. they offer a larger tipped liner, but it's huge. i wish there was one in between.