I drive a new Merc with mirror cams quite regularly.
They’re alright. You have to get used to not looking at where your brain knows the mirrors are, so maybe they’re safer because you dont have to look outside the cab.They aren’t that high definition. I expect they will get better as time goes on.
There is way less blind spot caused by regular actual real life mirrors. They’re better during daylight than in the dark. You don’t have to worry so much about whacking your mirrors on trees and ■■■■. They adjust themselves when you are reversing to give a wider angle view, which is good.