Now we are talking about personal myths.
In last 5 years I sold 2 trucks with over 300,000 miles each.
Actually I bought F250 with 300k on it and add additional 30k before selling for about the same amount.
Both run perfectly and sold them becouse I needed different configuration.
The 3rd truck was Ford 6l and that was POS, just like (I heard) V10 spitting plugs around.
Funny 1 more life experience. Few years ago I could cruise 100 mph on California freeways. Even I had Valentine One, for extra protection I was choosing other vehicle that would drive at that speed and follow it in distance.
On couple of occasions it was truck with V10 engine.
The only problem with following them was that when my diesel sedan could cruise 6 hr at those speeds, the V10 trucks had to make fueling stops every 2 hr.