Pretty good but not Perfect Rated 4 out of 5 stars
I used to use Organize Search Engines extension but as that does not work well with Firefox 3 I needed to find something else.
So I have just started using this extension and from my experience so far I can say it is pretty good. But it's still missing a few features that are needed.
Having the default folders always viewable is a bit off putting when editing even though they are not viewable when empty in the search bar. They should be deletable.
An "Are you sure?" dialogue would be good when clicking remove search engines, especially for the groups which can all be removed far too easily by mistake.
It would be nice to have some search engines outside the groups. Groups are needed to make a large number of engines usable but there are a few search engines which could do with being outside groups such as Google as I don't want to have to go through sub menus to find regularly used engines.
Having multiple sub menus would also be an advantage for people who like massive amounts of search engines but like them well organized.