"Firefox is a great browser. However, it's a tad on the bloated
side (even though the new version are definitely better!). Also,
Firefox is focused on cross-platform compatibility. That's great,
but sometimes that also means that Firefox won't be able to take
advantage of Gnome-specific features, including the unified look,
better language support, and HIG-compliant settings. If you've been
feeling these Firefox blues as well, Epiphany could be the
answer.
[...]
"So is Epiphany right for you? Well, maybe. You should probably
be using Ubuntu, not Kubuntu, Xubuntu (or the other derivatives).
You should also probably prefer ease-of-use and simplicity over
power (not that Epiphany doesn't have power). And you also have to
accept that Epiphany won't have as many add-ons as Firefox,
although there are a lot. If you're OK with all of the above,
Epiphany is a great option."