I friend of mine has a 2003 F-250 with the 7.3L Diesel for sale that I am going to look at tomorrow. It has 75,000 miles on it, and I know it has had meticulous care (he is a retired heavy diesel mech...
I think that 7.3 was a great engine for it time, but it was really loud, maybe louder than the Cummins. However, for towing at that time, it couldn't be beat.