
LG
45GX950A-B
Huge, immersive OLED, but 800R curve distorts productivity.

Running these analyses costs money. Buy through my links to help keep lights on! I may get a small commission.
After agonizing for a month on my birthday present to myself, I finally purchased the LG UltraGear 34G630A. Very happy with my purchase. Got it on sale for $400.
Tbh I've looked at both of these before. The LG 34g630a-b gives you that ultrawide experience which is great for immersive games, but the Lenovo Legion R45w-30 has a higher refresh rate at 240Hz if you play competitive shooters. For the price difference, i'd probably lean toward the Lenovo since the extra refresh rate matters more for gaming than the ultrawide format. Both are solid choices though - check if either has local dimming or better color accuracy if that matters to you.
# 34G630A is quite good, # 1. WQHD 240Hz with PXP/KVM function # 2. Good calibration, deltaE<2, actually <1 normally # 3. HDR400 and Freesync Premium Good for both office and gaming
Personally if it were me choosing between these 3 options, I'd go with the LG. I've had great personal experience with their displays, it has a higher refresh rate (although you realistically won't hit 240 in most games at 3440x1440), HDMI 2.1 and type c on top of the USB hub (although 15w of power delivery won't be very good for anything other than phones.) None of these options, or any others in this price range, are going to offer a great experience with HDR, so even though they're technically certified for it, don't expect much or make your purchasing decision based on it.
If your budget can stretch a little further, you may want to consider the LG UltraGear 34G630A-B. I've been using mine for a week (80% work and 20% gaming) and it's good for the price. The PbP mode has been impressive.
I don't have OLED money.. but I do have a LG G6 34" ultrawide and aside from the blacks not being as good as my ps portal I do very much enjoy the ultrawide 21:9 especially in civ and spiderman.

LG
45GX950A-B
Huge, immersive OLED, but 800R curve distorts productivity.
LG
39GX950B
39-inch 5K2K OLED: great clarity, comfortable curve.

Samsung
Odyssey Neo G9 G95NC
Massive 32:9 mini-LED; great for productivity, but buggy.

Alienware
AW3423DWF
QD-OLED gaming king; poor text, fragile screen surface.

Alienware
AW3425DW
QD-OLED gaming; good value; but VRR flicker and fuzzy text.

Ranked #1
LG - 45GX950A-B

Ranked #1
Samsung - Odyssey Neo G9 G95NC

Ranked #1
LG - 45GX950A-B

Ranked #1
Alienware - 38 Curved Gaming Monitor - AW3821DW

Ranked #1
Samsung - Odyssey Neo G9 G95NC

Ranked #1
Samsung - Odyssey Neo G9 G95NC