I have 2 friends with F350's with the 7.3 one has 300K and the other has well over 500k on the motor. Neither of them have any desire for a modern diesel and they both love that old 7.3.
Personally I am a year in and 15K miles on a '17 model year 6.7 and don't have anything to complain about as the truck and motor put a big smile on my face every time I get in it. The modern diesels do use DEF. Mine uses so little DEF it's hardly a concern or expense worth talking about.
