Interesting.
Last year I received a package from Superhot, from the USA, and he sent it with USPS as First-Class International Mail. I was able to track it not only in the USA, but within Hungary as well. (maybe because that was registered mail, or am I mixing something?)
The funny thing is when I wanted to send a similar package back, at the post office the staff said that the tracking number would work only within the Hungarian borders... But I was able to see the stops even in the USA...
Anyways, no matter who sends this package to me, must send it as registered mail, since the Hungarian postal service is not the best in the world...and I was too nice with them.
Same thing here, from 15 mail to the us with registered mail only 5 of em have detailed stops, the rest just said that the mail is in transit. Maybe the 5 just get lucky, or some mixed up? all i care is the mail arrived, otherwise, i send another one (only happened once to canada).