If your website has a lot of downloadable content that you want to protect from hotlinkers or autodownloaders and STILL make your content easily accessible to non-registered users, then this is the plugin for you. I loved it so much I even ended up buying the Pro version, and its absolutely worth every penny.
The only thing I really don't like in this plugin is the search feature. I have well over 1,500 files on my site and it seems to be very "iffy" searching for individual keywords. I would like to be able to search for files in one specific category. Oh, also it would be nice to limit downloads for individual IP addresses, but they told me they don't support this feature yet. Hopefully they will in the future. With that being said those 2 issues I have with it are very negligible.
This plugin rocks and their support for Pro users is very fast. Thanks to whoever made this plugin!