I've got more than enough hours in ED (2k or so), although less so since the last major update with all the walking around stuff. It's great for passing a few mindless hours, exploring especially. It does get repetetive, and fast, but there are plenty of little stories you can go and take in. Wouldn't touch PVP as the grind to get good enough stuff is just too much for me, although aside from a decidacted section, the MP is on its way out anyway.
I can't particulary comment on SC as not touched it for a while, but I'd say it has more lengevity than ED right now, and is probably more of an experience story wise, I might resinstall it and see what it's like now and get back.