I bought a Xiaomi Mi 9, it's a really nice phone. Although it doesn't have a 3.5mm and SD-card slot the rest of the upsides make up for it.
Initial impression is good, everything works as promised although MIUI needs getting accustomed to.
I also tested out the dual-frequency GNSS, works nicely I can pick up GPS, GALILEO and GLONASS on both bands. ~~However there seems to be no SBAS support on the Xiaomi Mi 9 even though the Snapdragon 855 should support it, maybe it'll get added but looking at how it wasn't promised then I somewhat doubt it unless someone hacks it together.~~ Turns out that they're not always visible, the SBAS sattelites. The Mi 9 has SBAS support and it works nicely.
The under-screen fingerprint scanner works nicely, just as good if not better than what I've seen on other phones.