I've been using the app for very long time and I'm completely amazed from the first day. It's not only functional but it's also beautiful and user-friendly (yes, a very important point!).
I had problems with working constantly on things but now it greatly improved and I know where I lose my time and work on improving that.
Started using this in beta a couple weeks ago and can honestly say it helps to adjust my behavior and break the bad habit of scroll addiction.
I do a lot of marketing work via Twitter so I can't completely block it. Feedless let's me keep up with my @'s and notifications without letting me wonder off into endless scrolling land.