I have been using this for about a month, and this stuff works! My lashes are thicker, a little bit longer, and the number of lashes have doubled or even more. I have read reviews of those expensive lash serums and was a little bit afraid that my lashes would grow long, straight and be hard to tame, but my lashes are still a bit curled and very easy to apply mascara to.
If you live in the states, you can buy it from Urban Decays website, if you live in Sweden like me, or somewhere else, you can buy it from beautybay.com

