So let's fast forward for a couple years. All 6.0 Fords are gone from the IPOR stable. Perfect maintenance records, no tuners, nothing but problems. The head gasket and EGR are the least of your concerns with one of those lemons - fuel injection is fatally flawed with no aftermarket fix. We went through fuel injectors faster than oil changes... (Hot Shot Secret does not work, don't waste your money)
December 2011 my 07 F250 was running out of warranty and to be honest I just couldn't afford to keep it on the road if I had to pay for all of the constant repairs.
I looked at the ford 6.7 but it was brand new and I was fresh from getting severely burned on a $40k+ truck that was worth less than half that 5 years later. I ultimately bought a new Dodge with the Cummins.
I had looked at Dodge in 07 but they were junk inside... then Fiat came in... yeah, I laugh at that too but you can ask anyone that has ridden in my 2012 Dodge Megacab Cummins Diesel that it is the most comfortable, most powerful truck they've ever ridden in or driven. Fiat added interior comforts to match (and exceed) ford, and with 800 lb/ft of torque it's ridiculously overpowered. It also DOES NOT REQUIRE DEF.
We just got back a few days ago from a trip to Windrock ORV park in TN and my truck pulling 15,000 lbs averaged 10 MPG. Take that for what it's worth, the ford 7.3 that went with us (my dad's, bone stock 240k miles, dealer serviced it's entire life) towing a similar load got the same MPG so no "oh my 7.3 would have done better". (and the Dodge got home a lot faster because it pulled the mountains at speed limit +5 where the 7.3 pulled at speed limit -25) Power wise there is no comparison - the 7.3 is an absolute dog when compared to the new 6.7 Cummins... but it get's the job done. My brother in law has a 99 7.3 with over 450,000 miles on it - he's replaced some parts along the way but nothing you wouldn't expect in 1/2 million miles. Major engine components are original, new trans at 300k, still quite impressive. I would be proud to own a 7.3 and you will be too. (though your neighbors might not like it if you're an early riser, LOL!)
The biggest difference between all of these trucks is the price tag. You can buy a 7.3 for peanuts compared to strolling into a dealership and asking for a new Ford or Dodge. ($60k+)
If I had to buy an older tow rig I'd probably consider the ford 7.3 or a dodge 5.9. Both are incredibly durable/reliable/strong/noisy and cheap by comparison to the new trucks.
Stay away from the 6.0, there is NO WAY TO MAKE IT RELIABLE.