Hi vjf000,
I am not from Laminar Research; just a flight simmer from downunder.
I am not conversant with the difference between OLED and QLED but what I do know is X-Plane has always been designed to run with screens (monitors or TVs) configured to run at 1920 x 1080 or multiple screens in multiples thereof ie 5760 x 1080. This means you can use a screen of whatever size you can afford.
I understand X-plane has now been configured to run with 4K resolution but still works best with 1920x1080. Until this recent change the screen had to be configured (magnified) for anything to look reasonable or the 4K screen resolution had to be "dumbed down" but running at 60 MHz.
In relation to sbbasile's comments I would respectfully suggest it is his new "overkill" system that is providing the increase in frame rates rather than the screen type an size. I have seen nothing from MIchael Brown at XFoprcePC who produces YouTube videos in relation to using X-Plane, indicating a higher resolution screen will give you improved frame rates. Michaels videos can be found at https://www.youtube.com/user/col2mab/videos He does not support the 4K concept (a video about 2 years back). The only benefit is to swap the screen to watch television.
Laminar Research recommends Michael's business as the preferred supplier of PCs suitable for X-Plane within the USA.
Glenn