Dan,
You even make my point stronger. The guy should go for the 747 right now, when he is young. This way he will enjoy the a/c, the long-haul and everything, while he can still cope with fatigue and ever changing schedule.
After his enthusiasm subsides, he can go look for t&c. I also see myself leaving the 747 for a more "life-stylish" a/c and/or airline, but for the time being, I am happy. I know that if I will fly a 737 or 320 and see the 747 taxi by I'd be wishing I was in the 74...