Just two reasons mainly, Dell's support is generally considered to be much better than LG's and the build quality is better on the Alienware, also you can swivel it, not so with the LG. They are the same panel and performance is much the same, the LG does have one clear advantage though, an sRGB gammut clamp, which could be of use to some people. I have an RTX 3070 so the native Gsync monitor is nice to have, although that's not a deciding factor it's more the build quality and support.
I actually have an LG 27GN850 aswelll as an AOC VA Ultrawide and I don't really have any issues with the nano IPS contrast ratio tbh, it's motion handling and colour reproduction are very good, much better than my VA's. While contrast isn't amazing it is 'ok' and it's quite a bit better on the 38" pannels it seems anyway. The LG I have also has the same stand as the 38" model, the newer more angular one it's a good stand, but I do like to have swivel ideally, at times anyway. Compared to the LG though the VA panel I have is quite blurry when you move about rapidly in a game and look at a fixed point, but I do love 21:9, how much better the motion handling is on the LG nano IPS panels is quite startling when you see it side by side for the first time ...obviously the OLED is even better but we've already been there
Thanks, a lot to go on there!
Agree about the blurriness in VA vs IPS, the increased contrast makes it better in SP games (thinking stuff like Metro Exodus, Cyberpunk etc. with quite a lot of dark sections and dramatic lighting) but playing more competitive games like PUBG, I do sometimes regret swapping out the Dell, as it did feel smoother despite being lower refresh...
Definitely very tempted by either the Alienware or LG, longer (and better) warranty is definitely a plus point considering I'd be keeping it long term (also appears you can extend the Alienware warranty to 5 years for ~£100).
If I was using it for purely gaming then OLED would be a clear winner, but the thought of ending up with a cross of window borders in the middle of the screen due to screen burn gives me nightmares