Just speaking from my own experience, my 97 F-350 7.3 spun the guts of it's automatic transmission at 74,000 miles and then promptly ate it's 3rd cam position sensor. My 2000 F-350 7.3 is still pushing hard on it's original automatic transmission with 214,000 miles and has only munched one cam position sensor - about 1000 miles ago.
I can tell you I ask a lot from my trucks and they have NEVER let me down. I have pulled many a lumber truck out of the mud (including a cummins powered boom truck)
and have given several cement & tri-axle dump trucks the extra umph they needed to get out of each of their predicaments.
Although I'm no longer looking to test my current transmission I'm sure if needed it would be up to the task.