Xiaomi has crippled smart unlock so it only works with their branded bluetooth devices, and doesn't work at all with Wifi. Between that and the relatively slow fingerprint reader (compared with dedicated hardware) unlocking is a PITA.
It's also only a so-so phone. Because they wanted maximum possible screen area the speaker is right on the top of the phone, so you have to position your ear really precisely to be able to hear through it properly. It's ok, but not great. I think I'd go for a phone with a top bezel and /or a notch next time, far more practical.