Are the 6.0's as durable as the 7.3's?
You'll get 3 answers.
1. No (Most 7.3 owners)
2. Yes (Most 6.0 owners)
3. Depends (all the other people lol)
The 7.3 has proven itself... the 6.0 is still trying to. Time is not on its side yet. I have yet to hear of a 500,000 mile+ 6.0 but then again the first year or 2 of the 6.0 was hit or miss as to the "quality" of the the motor. Best bet is to become a premium member here on the forum and get an OASIS report on the truck. If the truck checks out COMPLETELY, I'd say it's not a bad deal. If it was going to have problems (motor wise with it being an 04) they would have surfaced by 94,000 miles.
enjoy and welcome to the site.