I have sent probably 20 sails with E-Go all over Australia in the last 5-6 years with no problems. Depot to Depot
One thing I always do though, is take at least the minimum insurance. This means they give you a big red printed sticker to put on it that says:

I usually put two of these on the package.
I have not evidence to prove this, but I think this makes a difference to the way most drivers and handlers treat it. No one wants to be up for paying the insurance if they lose it.
IMHO, also a good idea to write the address details all over the box, so if the label is damaged, it can be identified.