My truck has been running as it is for the last 2 years and 35K miles(it is my DD, the F150 I bought for that purpose turned out to be too expensive to run if it isn't working) with no issues, with lots of towing in the 18,000-23,000 GCWR range. Very few of those 33K miles were easy highway miles, I have a lead foot, and almost all the highway miles I put on are towing. If anyone's truck is going to die from making big power, it will be mine, I'm not scared of big boost or high egts, I want to find the limits for reliability and longevity; so far, I have yet to come near finding them and I have 3 spare IDI's for when I do find them. And, I will share my findings, not just quietly replace what broke and not say anything.
Don't think I have any big money in my truck either, I paid 4x as much for the turbo than I did for the truck itself, and I got the turbo kit for $1200 with a new turbo...
My 6.9 will easily walk all over an OBS 7.3 in stock form, and no question would have ate my 00 Super Duty for lunch. Heck, I ran with an 05 Dodge Dually one day, and he only got me by top ending me, we were very nearly even until I ran out of rpm.