Been looking at this Dell Q2721QS monitor for work and gaming.
But has anyone have any experience gaming on the monitor at 1080p since this is a 4K monitor?

I haven't try the monitor that you considering but I'm using this instead and is fantastic quality. No complain for high res gaming man.

https://store.acer.com/en-my/monitors/cb342ck-uwqhd-c01

wasnt great gaming monitor.. u might experience color distortion

the refresh rate is just 60hz, not really recommended for gaming, try look for those monitors that has 144hz n above such as acer nitro xv270p

https://store.acer.com/en-my/nitro-xv270-p

1080p will look ok on 27" with some pixelation. Anything bigger than 25" will require 4k.

You will get a lot of screen tearing playing on 60hz (happens to my work 27" 1080p dell).

Get a better screen with higher refresh rate) for both gaming + work duties.

Do not confuse by FHD (1080p) and 4k (2160p), and also 60 Hz refresh rate with 144 Hz and refresh rate.

One is the pixel resolution and another one is refresh rate.

Honestly, most of the time I don't really fully utilized the 144 Hz on my 1080p FHD monitor too. 4k is having larger screen resolution.

If you wanted to have optimum gaming experience, the refresh rate is the one you need to look into. For Dell S2721QS, it only support 60 Hz. Recommend atleast 120 Hz (best experience with 144 Hz). But this is also depend on how much you do on gaming and what games you playing. Like most MMORPG and strategy games, you need 60Hz to 90Hz will do. If you on max graphics setting for FPS (Cyberpunk 2077, Call of Duty: Vanguard) or sport games (FIFA and NBA), you might need minimum 120Hz). Personally, I tested Cyberpunk 2077 on 144Hz, 120Hz and 60Hz. Minor graphics detail improvement from 60Hz to 120Hz and 144Hz. But honestly I don't fully utilized 144Hz on 95% of my time with my gaming experience.

You can consider Acer Predator XB273UGS as well. It has fast refresh rate at 165Hz and really great colour depth. I'd say it's a good one for gaming.

https://shopee.com.my/ACER-PREDATOR-XB273UG...8462.5816177106