This isn't meant to be a comment disparaging WordPress either, but the idea of "publishing posts on a Facebook page". Facebook has been cutting down on that for a while; if you want the sweet FB juice you better pay up. Although, if you really automate the entire thing to the point that I (as a publisher) don't even realize it's happening, I guess it's better to use it than not. My point is that since these days you can only get (relatively) a trickle, the value of this plugin is much smaller than a few years ago.
(Also my mind would blow up if 10 plugings like this didn't exist already)