I'm rooted (de la Varga) but stock on MI1. Phone said update was available, downloaded it, but when I tried to install it I got an error. I've tried it twice. It won't install. I thought there was somewhere in here how to manually install it but I can't find that either. Maybe I'm just having one of those days...
This guy managed to keep root, supposedly, after coming from rooted MI1 - a pretty convoluted way, but interesting nonetheless:
xda-developers - View Single Post - [OFFICIAL] 4.3 Update - Changes/Differences/Discussion
I'm staying on MI1 until Safestrap and Root is complete before I update to 4.3.
(Verizon) Samsung Galaxy S4 - Rooted - VRUAMI1 (STOCK) | (Verizon) Casio (GzOne) Commando 4G - Rooted - C811M020 (STOCK)
I give up! I'll give it a week or so and someone will already have a way to flash/install/Odin the new update with root... I'm going to make dinner where I can feel like I've accomplished something. =)