I have a rooted GT-I9300 running stock 4.1.2
It was rooted back in the days of ExynosAbuse, and since then SuperSU survived all OTA upgrades up to build JZO54K.I9300XXEMG4
My current status is "Normal".
There's currently a ~400Mb OTA pending, which I suppose is the 4.3 upgrade.
My question is, what are the chances that OTA (or Kies, or ODIN maybe?) update will complete with SuperSU (latest, Pro) surviving?
If not, how bad is to have a broken SuperSU on the phone?
If doing an OTA in these circumstances is a bad idea, what is the best route to upgrade while maintaining root?