I am new to this forum, and this is my first post. But as far as having to work the 7.3 for best results. I can say that my 03 7.3 that I bought new in Aug. 02 is probably the most reliable, best running vehicle that I have ever owned. I do pull a 30 ft. 5th wheel camper a few times during the summer for a few local trips and 3 or 4, 200- 600 mile runs..
The rest of the time it's my daily driver, I am retired now, so mostly errands, go here and there, short trips 5-35 mile range. This venicle runs better all the time and I only have at present 39,575 miles on it. So if you can find a 7.3 that you like and have it checked out by somone familar with diesels, don't think that you have to drive it like a long haul trucker. They have great engines, if properly maintained
Good Luck, Ed