Upgraded my 2019 40i to firmware version.53 last week. Using it for the last 3-4 days, my impressions are the following:
CarPlay with ios13.1 on my iPhone XS Max is significantly more stable in connecting. Zero drops in this period. Once I thought it would not connect, it took its time but connected.
Had to reset my data privacy and climate settings to re-enable remote start.
More consistent and accurate and better synced maps across the three displays (hud, dash, main console).
Got one warning about emergency call malfunction that went away on its own.
Seat ventilation only showed heating option once but has since fixed itself
Display brightness works fine, as do cornering lights.
Caring car app doesn’t load yet, but all other Bmw apps seem to be installed.
Remote 3D view on the phone is faster and more consistent.
Overall, feels stable and solid, more like the rest of the vehicle. One can’t help but feel that should have been the level of their initial production release.
Not tried Apple Pay yet, don’t use it much , so i have disabled it.