Don't quote me on this, but I'm pretty sure the update will still fail around 27%. There was something floating around here that said rooting the phone removes a file or something that the update looks for before allowing it to completely install. Obviously you have to be rooted to use SuperSU, so it most likely won't work.
yep, i did this and now have supersu in /system/app and su in /system/xbin, but root doesn't work and i can't get rid of them. the only real downside i've found so far is Isis Mobile wallet thinks the phone is rooted and doesn't work.. but i don't use Isis anyway.
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