I'd agree with FTJ, to an extent. Out-of-the-box and hit the ground running, yeah shes got it right. But if you want to work things a little, you can certainly use FFG Star Wars in any era. But if you just want to grab the book s and game in another era besides Dark Times/Rebellion, then I'd say go with Saga. At least until some more material is published.
FFG Star Wars is a good system - not perfect by any means, but a pretty cool system overall. Saga is still my favorite Star Wars system, but my group is starting to lean more towards FFG. I'll still pick Saga, but it's no longer supported officially. That's probably the biggest boon for FFG - it's fresh and current. How long it lasts remains to be seen, but its worth playing a short campaign and trying.