I have 3 7.3L engines for my company. One has 205, 170, and 70,000 miles. Overall they have been good trucks. Ford does have the reputation of having unreliable transmissions, but the 'newer' 1999-2003 trucks should be more figured out. The 7.3L is def. a 400,000+ motor. I do not plan on getting rid of any of my trucks, no matter the miles, before it is there time. Change the oil every 5,000 miles. Check the oil pan, they have a tendency of rotting out. The motor will most likely outlast the truck with normal PM. Every brand has expensive parts to replace vs. cheap parts. It depends on the truck. The 7.3 is very straight forward and simple compared to the duramaxes. I was a mechanic and have worked on both a lot and chose ford for a reason.
2002 Ford F250 - XLT - 4x4 - ext. cab
1997 Ford F350 - XL - 4x4 - Diesel - Insert Dump
1997 Ford F250 - XLT - 4x4 - Diesel - some extras
Kubota L3540 - HST - Loader - Backhoe
Kubota L3940 - HSTC - Snowblower - Belly Mower
Scag Turf Tigers
Stihl 2-stroke equipment