What are the advantages/disadvantages of using CSS preprocessors?

Advantages:

• CSS is made more maintainable.
• Easy to write nested selectors.
• Variables for consistent theming. Can share theme files across different projects.
• Mixins to generate repeated CSS.
• Splitting your code into multiple files. CSS files can be split up too but doing so will require a HTTP request to download each CSS file.

Disadvantages:

• Requires tools for preprocessing. Re-compilation time can be slow.