alrights guys I didn't see this anywhere in ur forum so here it is, after exchanging my s4 for a replacement, I got it with 4.3 and all this Knox nonsense already installed, Now I don't really care that much for samsung's warranty but I went out and look for a way to root our latest without triggering Knox counter just head on to the thread below and check it out... it has a catch but I would say it's worth the trade off.
http://xdaforums.com/showthread.php?t=2565758
http://xdaforums.com/showthread.php?t=2565758