I can only share my experience, but when I bought my 2001 5.4 with around 100K miles, there were a couple missing exh studs. I finally replaced them all around 110K miles. As for plugs, they have been changed twice, once at abour 100K and again in another 75K. They have been torqued to around 24ft/lbs each time with zero issues. I'm now at 200K miles. I assume the V10 is nearly identical.
Agile Ride improvement package