My previous monitor was the same resolution. I've had a Samsung G9 for 4 years. The MSI has the same dimensions but is far technically superior.
Oh I didn't catch the 5120x1440. That is actually my ideal size as well. Although I prefer 2 separate 2560x1440 monitors. I find bezels help me compartmentalize lol.
I was in a Best Buy two weeks ago and they had a 34 inch Alienware QD-OLED AW3423DWF, open box, excellent condition, for $450. I didn't even want a new monitor, but I couldn't pass up that price. People don't even sell them that cheap on FB Marketplace. And it still has the manufacturer warranty. It is my first OLED monitor and my first ultra-wide, and I don't think I can go back. Amazing.
I've read that OLED screens can make the edges of text a little soft. So they are great for media and gaming but less so for productivity. I've been tempted to get an OLED TV but the burn in factor worries me. I might just wait for microLED to go mainstream.
I had the same concerns, because I use my PC for work and gaming. On this specific monitor, the PPI is good enough that I don't notice the text fringing at all. I have seen it on some monitors where the PPI is not as dense and it would bother me in those cases. Also, I watched a few videos on stress testing OLED panels for burn in and the issue seems to be managed pretty well at this point. A Youtube channel called Monitors Unboxed did a torture test of 15 months of static content, which is not how I would use the monitor, and they had to use visual enhancements to show the burn in. I figured at the price I got the monitor, why not? I'll just abuse it and if it becomes a problem, I'll deal with it then.
I have a 55" LG C9 (2019), 65" LG C1 (2021), and a 42" LG C3 (2023) that I use as my main monitor. Zero burn in.