Poco M3 is a great device for its price range. As it is an entry-level device, there is no use in comparing it with mid-range or high range devices. The only problem I saw in M3 is that little UI lag it has. However, it's already fixed in the EU 12.0.4 and 12.0.5 updates. We will also get the update soon on the global version.

For now, I have done these two small tweaks and noticed a significant difference. So, if you are also having that lag issue, try doing these things until they send an update.

(1) Turn off animations

Enable Developer Options, then go to Settings - Additional Settings - Developer Options and either turn off or select the lowest values (I suggest you to off them) in these three options:

Window Animation Scale
Transition Animation Scale
Animation Duration Scale

(2) Turn off MIUI Optimisation

By default, this option is enabled. You can also turn off this one. This is the last option in Developer Options.

Do those two changes and use the device for some time. You should feel a difference.