Funny thing is I don’t know, all I know is that every video review including the one from (DDJT’s Phil Morse) finds them not to be ideal. If the meters give clear accurate /selectable individual PFLs and master out, well that’s good enough for me.
I just re-read the review and apparently it’s about the fact that the single stereo level meter has to show both master and cue levels, but the way this is implemented is not optimal and could lose to some confusion.