The most impressive thing about it was its syntax, which I liked very much! It's not so hard for me as other languages (like Java) because of this feature - you can write your code in an elegant way with minimal effort compared to others like C# or PHP etc., since there are many ways how one could do something similar without using classes at all. Also it runs well under NodeJS environment. There isn't anything bad yet but maybe some people would dislike writing modules when working within nodejs? If anyone wants more information then just ask :) This product has helped us solve our problem regarding creating web applications faster than before by reducing time spent developing them while maintaining quality standards thanks to coffee script.