Just because it's new to you, perhaps, that doesn't change that it's an old model phone.
There's no more updates coming for it, so there's not much you can do to kill it and if you do, you can buy another one pretty cheaply.
Moreover, unless you're going to do virtually nothing with it (like install apps, for example), it's not a very good device unless it's rooted. There's so much bloat on it and limited core storage space, that unless you root and do something like Link2SD (so you can move apps to the SD card and freeze some of the bloat), you'll end up tossing it aside in favor of something more modern.
Don't get me wrong, I have had an F3 for almost a year and overall like the phone. But it has some pretty significant drawbacks, and I bought it knowing them with the intent to root and get around the worst ones.
It does work very well as a phone, though, regardless whether you root it.
Good luck.