Just like how unlikely it was that the Acer would be a significant improvement over the XG438Q, the same applies to the XG43UQ; same panels, very similar results. A little more brightness isn't going to change muchOk so I got some answers for a few of my questions I asked Acer supports.
1. This monitor does not have DSC.
2. I asked them:
'Will I need to use 2x DP 1.4 cables to achieve 4K @ 144Hz, and if so, will g-sync still be active on this monitor when using 4K @ 144Hz.'
Their response was:
'No support when 2DP mode'
Not entirely sure how to interpret that response., but it sounds like it does not support g-sync when using 4K @ 144hz?
3. There is 16 local dimming zones.
Sounds like I may have to wait for the ASUS XG43UQ.