I'm writing this just after receiving the product, so I might update later, but wanted to share my thoughts right away.
I've tested the eyeliner both on my hand and (a bit hastily) on my eyes. The positive is that it really stays put, no joke about the durability here, and that's good because I have watery eyes so it's hard to find something that holds well enough. Almost TOO well, I can't get it off haha, but better that than the opposite.
The downside, which I've also seen other reviews mention, is that it's very hard to work with. The product itself is quite thick and sticky, and the brush is very strange. I mostly have experience with felt-tip pens while this is a brush with bristles, so it's a bit different, but it doesn't feel good.
The biggest problem is that it's not sharp enough, so getting thin lines and sharp edges is terribly difficult. You have to scrape off product on the edge and try to shape the brush into a point. Also, the brush feels too soft and bends too easily, so it's hard to get it to go where you want, but this might be because I'm used to felt-tip pens which are quite stiff. I also find it smudges a lot, so I got a lot on my eyelashes and it didn't look good at all.
All in all, it feels like this would be a PERFECT product if the application was better. I really love the durability! I'll try to learn to use it better or maybe try applying it with a different brush than the one that comes in the package? Also, I need to figure out how the heck to get it off, haha.
I use a crazy amount of lip balm because I find it extremely uncomfortable to have dry lips (and by "dry" I don’t mean in the usual sense, but dry as opposed to wet haha), I always have to have a thick layer on them or else I go totally crazy. Decubal’s lip balm is by far the best I’ve ever tried! Really thick and lovely, it feels incredibly satisfying to use and lasts a long time. I’ve gone through so many tubes, always buy several at once!