Rated 5 out of 5 stars

Great tool! But I find ANY toolbar should ALWAYS have a toggle hotkey and a toggle button that can make the toolbar quickly appear and disappear. Shouldn't be too difficult to implement. Clicking one's way through "View > Toolbars" is just too awkward. At least, under "View", a toolbar should always have one of those underlined letters (in that case one could create a hotkey with some macro program). ;-)

This review is for a previous version of the add-on (3.0.2). 

...and if you like to participate in the official feature request: https://www.mozdev.org/bugs/show_bug.cgi?id=24715 {New feature - button to toggle quickfolders toolbar}
or you can raise a new bug from here: http://quickfolders.mozdev.org/bugs.html