Here at Zoocha we use preprocessor for almost all our frontend work. Predominantly we use SASS although some projects are on LESS, partly for historical reasons. No-one can deny that it’s a really powerful way of writing CSS, giving you access to variables, mixin functions, and the apparent Holy Grail: nesting. The thing about all of the above though, and I think something that often gets forgotten is these are all tools to make the developer’s life easier. The result is still compiled down to CSS.