Is there a way to find out what software version is going to be sent to your phone?
I have a Galaxy S4 and have just looked (settings - more - about device - software update - check for updates) and it says an update is available, but doesn't say what it is.
I'm reluctant to do the update if I can't check to see if anyone as had problems with lost data, bricked phones etc. My handset seems to work fine so I don't want to update it if I'm not going to get any benefit but potentially risk breaking it.
How likely is it to bork my settings or data if I do the upgrade?
When I had my S4 the jump from 4.4.2 to 5.0.1 was a bit of an issue. I ended up having to do a factory reset to resolve some of them - although there seems to be have been an update for the phone since I changed to the S6.
However, personally I found upgrading to 5.0.1 worth it - the S4 felt like a completely new and improved phone.
With you going from 4.2.2 all the way up through the updates, I definitely would back everything up before attempting to do it.
But as there are also security risks with older versions of Android, it's another reason to do it.