The scan feature is extremely fast, the fastest from the extensions I've used of this nature thus far. However, the lack of a delete all or a checkbox system to make that part of the process faster makes this utterly useless unless you only have a handful of bookmarks. At which point, you could do everything this extension does manually anyway. To make matters, better or worse, when deleting a bookmark you have to manually confirm its deletion.

I don't know about other users, but the reason I need an extension like this is because my bookmarks are in the 10,000 range (actually used to be more like 50,000 but it got better). Because of this, not only is it important that the scan feature is reliable and relatively quick, but the ease of what comes next is also important.