Interesting question. I'm struggling to find out my self. I am afraid I will have some issues with face id. Use my phone in a carholder in my car and with fingerprintsensor that works flawlessly. Same when I have my 8+ at my desk, so easy to unlock with a finger. Worrying that face id don't work as well in those places as fingerprintsensor
FWIW I haven’t had Face ID fail yet. I’ve used the phone in near darkness and while laying flat on the counter. It’s so quick sometimes I don’t even realize it’s already worked until I see the little lock unlocked. I use CarPlay so would not need to use it in my vehicle so that part I can’t help with.