I send/receive hundreds of packages a year, ive had a few held up in customs from time to time and a few get delayed for some reason but have not had a package go missing this is the joy of track and trace and to send your ecu is cheap.
As for the ecu getting bricked in this day and age its very unlikely an all the years i have been doing this ive had maybe 4 ecus take a crap,
The funny things all these ecu's were having updates via buds at our Can am dealership in saying this i did manage to "Fix" the ecu's with rewriting new software with my own system.
Jase