This is not relevant. It's virtually the same panel, just a slightly newer (brighter) revision. In all aspects, on paper anyway, it appears identical, save for the brightness. The XG438Q exhibited all the worst (and most typical) faults of a VA panel, ones that almost all users have reported, so it's hardly limited to just a few bad panels... there is no logical reason to assume a slight revision of the same panel will magically resolve all these (serious) problems, and certainly not enough to justify an even more expensive price tag. HDR-1000 certainly won't be enough if anyone thinks different, the backlight just isn't up to task here. Again assuming it's the same as the Asus which it most likely will be... it certainly isn't FALD anyway.
I'd love to be wrong, as I was very much looking forward to these 43" monitors after years of waiting for something like this... but I strongly suspect the Acer will be a further disappointment.