well i was instructed how to properly update which i knew how to but wasn't quite sure about boot-loaders. but what gets me is i flashed the factory image and even on stock with no root, no rom, no kernel i had issues with network dropping, FC'ing apps, random reboots daily, Samsung Knox still causing issues daily (i deleted all apk + odex), only Philz recovery decided to work too TWRP 2.7 4.4 Boot loader edition wont work for anything nothing gets applied at all in that recovery. The only good thing KK has given me is slightly better battery.
YET on 4.3:
Stable, Works, No Samsung Knox issues, Working Recoveries, No network issues, No audio crackling issues
The only reason im still on KitKat is the fact that im waiting for a ROM that will be actually good that's near stock and odexed.