And what difference does that make? Each plays just about anything you throw at it Try & se which one YOU like most (for whatever reason)
VLC doesn't support 1080i and you can't use external subs. Since KMPlayer is sold its development has been slowed down, so I recommend software from same author - PotPlayer.
Why ask which player is better. If you like both programs install and use both then see what pattern develops.
KM Player sometimes VLC doesn't work for me, kmp is improving with updates, some files are better on kmp