When I tried rss with Feedly before. I wasn’t getting blog post comments. I don’t think reddit/HN comments either but could be wrong there.
You get the title which is a link to the submission, a picture and a link to the comments. I'm on Android so hitting either opens a webview (powered by Firefox) with an X in the top left which leads back to feedly. I also have scrolling past a submission set to mark it as read.
Admittedly something which handled unread comments and notifications for replies could be more engaging, but I feel like I get enough HN as it is and I want to remain somewhat productive.