I've worked on the airplanes that Fedex, UPS, Purolator and other use (USPS too, through the above people) Every night, while waiting for these airplanes to depart, I'm sitting in the van watching the "cargo smashers" as we call them, load the airplanes. They're brutal. They're (stereotyping here) mostly riff-raff, about the only kind of person that wage and a split shift could attract, and simply don't give a rat's ass about you, your package, it's contents, or the person it's going to.
The bottom line is, if you want it to get there in one piece, package it like it was a vial of nitro glycerine that you DON'T want to explode.
and yeah, postal service is definitely the way to go.
I couldn't believe it, I shipped a small box from canada to hong kong through the post and it got there in 4 days!