I'd love some feedback, and it's still pretty experimental, so there will be some bugs, but I've got it working for most full-text RSS feeds.
Currently, the interface is very simple: you give it the URL of your blog, RSS, or Atom feed, and it will give you a link you can use to share it. This "share link" contains downloads for ePub and Mobi files, and the downloads will always stay up to date with the latest content (I use Superfeedr to poll the feeds on the backend).
Let me know if you have any questions.