[Q] Questions/Help topic

First of I want to thank everyone that shares their knowledge on here.
I originally came here to root my phone so I could use ARlib. I had trouble getting that to work and tried ARU and it's working great.

Now that I have it working I'd like to protect what I have. I've been reading the forums, but even in one thread people sometimes contradict each other, so it's been hard sometimes to follow it.

I'm on 4.3 with a VRUEMK2 build. I flashed using your saferoot guide here: http://forum.xda-developers.com/show....php?t=2565758

My questions are:

What is the best/safest tool to make a backup?
How do I stop 4.4 OTA?
Is it ok to use Kies to sync or is there something better for Outlook?
I see a lot of recommendations for ES file explorer, should I get the plain one or the manager version?
Also since I can't ask in that forum and don't see it answered there, what is the advantage of the GPS injector for ARU vs. just using the phones GPS?

Thanks