## Why do you use SASS/Compass?

I chose Sass/Compass specifically because I had researched the big three (LESS, Sass, Stylus) for a few months before the start of a new project, over that time Sass felt right. It also helped that I had a few friends who made the jump to Sass before me. And I know (went to college with) Brandon Mathis a core contributor to Compass.

## Why do you like it?

See Sass/Compass Pros below.


## Sass

I've been using Sass so I have first hand knowledge.  In general most of what I see are pros work for both Sass or Stylus in that they support variables, mixins, custom functions, conditionals and looping.

### Sass/Compass Pros

* It's not CSS
* Both are well documented, with examples
* Source map integration with Chrome and Firefox

### Sass/Compass Cons

* Error reporting exists, better than LESS but not nearly as good as Stylus
* Can be slow with preprocessing. Although, if you don't use compass their is an alternate solution using [node-sass](https://npmjs.org/package/node-sass), with the [grunt-sass plugin](https://github.com/sindresorhus/grunt-sass) 


## Stylus

I have yet to use Stylus so I did a little more research, below are my thoughts.

### Stylus/nib Pros

* Allows 3 types of syntax. Though this can be a con in that a file could become a mess of all three syntaxes. Easily remedied by code standards.
* Great error reporting, better than Sass
* nib similar to Compass, providing CSS3 mixins

### Stylus/nib Cons

* nib is not as robust as Compass

### Stylus/nib Pro or Con?

* Transparent mixins.  I view this more as a con, explicitly identifying mixins and variables avoid the potential for overlooking functionality.
* nib contains all mixins, no need for importing. Couldn't find much on performance, but with Compass you can import only what you need.

## Conclusion

As I've worked through these answers I can see myself leaning toward Sass/Compass. The explicitness of Sass in my opinion is better than Stylus's implicit approach, which seems to be swaying me.

I've heard it said a few times and completely agree, "any preprocessor is better than not using a preprocessor".