I have a 2007 F-350 6.0 Powerstroke crewcab and I commercially haul travel trailers for a delivery service. Mine runs great and is reliable. I know of all the problems with these engines and also notice that 90% of these people that do have the problems are all guilty of the same things.....not changing oil regularly, not flushing coolant occassionally, and chipping them for big power and rodding the crap out of them.
Adding too much power adds cylinder pressure that pushes the stock head bolts and gaskets to their limits, not changing oil and coolant plugs up the oil and egr coolers, as they have very fine passages, plus not changing the oil adds to injector problems as these ones are operated off high pressure engine oil.
As long as it is maintained, I wouldn't worry about it at all. I also had a 2007 of another brand and this 6 litre gets way better fuel mileage.