It is useful, but it is not a downloader! It opens the image on another tab, so you can download it yourself, and that saves a few clicks. Would be ten times better if it would actually download the picture though, especially as it is called a downloader and nothing in the description tells you what it actually is! The second downside is that pinterest loads more pictures the more you scroll down, but the 'download' buttons don't so you have to click on the add-on button constantly to load the new buttons, which is quite annoying and therefore doesn't save that many clicks to download pictures actually.