If you really want to get it or ship it send it UPS or FEDX. Helps if you put a real box inside those flimsy flat rate boxes if you use the postal system but that doesn't help when they loose the whole thing. Very unreliable service.
I second that. I NEVER ship USPS if it matters. I prefer Fedx only because they are more convenient for me.
I have noticed the Fedx online calculator is almost always low when estimating the shipping price.
USPS lost and expansive item I shipped to a friend once. They had a record they did not deliver it but ( shock!) they had no record of which employee took it home.