Downloaded and activated this into wp 4.2.2 with twentytwelve theme. The plugin works okay and the support from the author has been fantastic but I've had problems using the Feedly mobile app and Feedly browser to view the RSS feed.
Feedly provides a feed overview in a "cards" or "magazine" style format and the featured images were not appearing in the overview, or appearing a long time after the post. Also, because of the way Feedly works, the plugin's image size or image position options had no effect so I was unable to assess these, apart from wondering why there wasn't a "full" option or what "post-thumbnail" was under the image size setting!