Epiphany is user friendly, light and fast. It caches better than Firefox. I also like their non obstructive UI.
I like the feature where web search, bookmark search and URL bar is all in one, and still works smoothly.
Bookmarks are arranged in a more human manner with topics and they are easily accessible through the URL bar. History is also unfriendly.
Epiphany developers have a good job in creating a user friendly browser based on gecko and will respect GNOME themes.
But for development Epiphany is not the best because Javascript console is missing and viewing the source requires extra effort.
I prefer Epiphany over Firefox for browsing.