Whenever I see images in an RSS feed, they are embedded in CDATA, rather than surrounded by tags.
In my feed, I would like the images to show up without doing that.<
I believe you can use items with good support by most rss readers, it is working flawlessly for us on mailchimp (rss to email newsletter).
See http://kb.mailchimp.com/article/how-can-i-format-the-image-content-in-my-rss-to-email-campaigns
EDIT: Here's a live link: https://blog.mailchimp.com/rss-to-email-enhancement-for-publishers/