What a time saver! Rated 4 out of 5 stars

Truly a time saver if you're experimenting with the CSS style of your site. Avoids the modify,save,upload,refresh,repeat cycle. Changes are reflected immediately as you type.

Only downside I've found is that it has trouble with relative url()s such as in a background-image.

This review is for a previous version of the add-on (0.3.6).