Mailing: Did I just get lucky?

I mailed 2 packages to Japan (one to Nagoya and another to Yokohama) from the western coast of usa via regular airmail.

The one to Nagoya took 7 business days and the one to Yokohama took 6. On top of that, I am really pleased that the packages didn't arrive duty due.

I am really surprised because I mail a lot to the Philippines, Malaysia and Indonesia, and it usually takes around 2 weeks (to reach capital city) and 2.5-3 weeks (other than capital cities).

I must say the Japan postal offices are very efficient. Did I just get lucky or is this nothing to be pleasantly surprised about?

I've had USA to Japan in 3 days and around 5-7 is common. It's a great service and Japan Post is unbeatable.

Packages from my mother-in-law in Japan arrive here in the SE USA in less than a week, letters I send to my wife when she is there take about the same, so I think your experience is normal.

I've had mail to/from NZ and Australia arrive in 3 days, so your experience is nothing unusual, no. Japan can be super-efficient in many areas. I have had packages take a lot longer as well, up to two weeks.

Whether duty would be owed or not depends on what is in the packages and how well the staff are checking. It's possible that the items you sent don't attract duty in Japan, even if they do in other countries.