The formula is really good, you can easily control how much colour you want, so it can be used for very intense looks, or just to add a little bit of sparkle. Dries quickly and after that it stays in place.
I'm taking away one star because the shade doesn't match the description exactly in my opinion. It's said to be ultraviolet that reflects into navy and pink, but at least my product is definitely dominated by blue. In shadow or darker surroundings it looks blue. When the light hits it, there are beautiful shades of violet and pink, but the base is definitely blue. Not violet, like I thought from description and picture. I still love it though, but I'll probably have to buy a different shade to fit my color scheme.