What are the advantages of enabling or disabling Samsung KNOX
Directly from Wikipedia :


  Samsung Knox provides security features that enable business and
  personal content to coexist on the same handset. The user presses an
  icon that switches from Personal to Work use with no delay or reboot
  wait time.1 The manufacturer has claimed this feature will be fully
  compatible with Android and Google and will provide full separation of
  work and personal data on mobile devices and "addresses all major
  security gaps in Android.


(Download Android Terminal Emulator) then 
for Disable : 

pm disable com.sec.knox.seandroid


and after disable,  maybe you need this again ;

Enable :

pm enable com.sec.knox.seandroid


And i suggest you, in the SuperSu never touch For Disabling the Knox.
it maybe harassment you and need for the second root process.(this is happend for me, but maybe you need to try it).
Also , read these articles :

How to Disable KNOX Security

HOW TO REMOVE KNOX AND PREVENT POSSIBLE ROOT ISSUES CAUSED BY KNOX

How do I Remove or Uninstall KNOX