Xiaomi.eu 10.3.16 is stable. After flashing, install magisk and search for Audio Compatibility Patch. Install this patch and you're set. The only issue I've had was Google Assistant's Voice Match, which, from what I understand, has been blocked by Xiaomi. Everything else works perfectly. The rom is debloated, fast, and Nova Launcher+dark mode makes it look good too.
It's still much better than the current versions of LOS, Pixel EXP., RR, etc. I flashed LOS and Pexp and they were way too buggy in this stage.