One of the few component (pull) web framework. It's philosophy you should learn, before you choose a web framework for a new project.
Ranked in these QuestionsQuestion Ranking
Pro Clean code, change of code philosophy
Clean structure helps you maintain your code for a long time.
Pro Save you a lot of work
To save your work you need to understand it's philosophy.
Con Long way to learn it.
It's philosophy is radically different to what you probably ever seen.