Luckily I havent had any issues shipping with USPS priority..... I do fear the day, however. It can become a mess pretty quick. I do not hold myself responsible for the actions of USPS if they claim it to not have arrived... If the tracking tells me its there, then sorry.... Go find it. Within the US, I have had to instances where the box hasnt shown up.... 2 incidents in 5 years, and yes I replaced the parts.
best of luck Brandon..