Generally, prime day, black friday, and other big sales are intended to clear out poorly selling products. Not generally the stuff people actually want.
I picked up the LG OLED 1440p 240hz panel for $600, still the lowest price that particular model has been. Just had to watch it for about 2 months. It bounced around from its launch price of 800, to 729, to 650, back to 729, then 700 for a while, etc.
The LG Ultragear IPS 240hz 1440p panel gets pretty good reviews, probably not quite as good as the Alienware which is newer I believe. But that is the price difference reflected.
If you want an MSI, this also has decent reviews, cheapest at MSI at the moment:
https://us-store.msi.com/Monitors/Gaming-Monitors/G274QPX?irclickid=QmlWuZ2pExyKWygwlA1MLXJqUkCxb33:iTlg3E0&sharedid=&irpid=79301&irgwc=1