Honestly I tried MIUI 12.5.4 on Redmi note 8 with clean installation but I'm very disappointed with the performance. It was very laggy , sometimes I received a call and screen doesn't turned on. When I opened settings and tried to navigate sometimes It was needed to scroll twice with my finger to see a response on the screen.
Visually it was better than MIUI 11 but I prefer a better performance than visual.
So I decided to went back to MIUI 11.0.7 stable.
And now my phone is running like a lightning