the old one is not really "better", in fact its actually more complicated to use and less compatible since, to my knowledge, it only accepts a YUV signal.
We're about to set up a z24x here and have it run via ultra studio mini-monitor, I have seen mostly good reviews from it the only "problem" is the uneven backlight bleeding but it seems to actually be the coatings on the panel reflecting on each other. Either way, for a 500 dollar color grading screen you really can't go wrong