60 degrees allows me to still see the gauges in most of the cars. No wheel or driver viewable and I use the virtual mirror just because the "real" mirror is no where to be found on my screen (yes, I've tried to move it, can't move it far enough.)
Only, in the MRT I usually go back to default because I see nothing of the car at 60. But then I usually quit racing the MRT after a few laps because the view looks so horrible at 90.
I think it's funny how people talk about realism, then post that they use a view that either puts them outside the car, sitting in the center of a 2 seater, or an FOV that makes it look like you are sitting in the back seat.