Yes, USPS major problems at Allen Park Michigan facility last winter, many news stories of trucks filled with mail sitting for 24 hours and more waiting to be unloaded. Sorting machines being removed from various USPS facilities have been responsible for slow downs.
I have clam shell mailbox for my neighborhood, forget about resolution of lost package if your package misplaced in someone else's box!
And then USPS and customs, forget about it! I purchased Technics SP10 MKII few years ago, from Australia, shipped via Australian Post, transferred to USPS upon arrival here. Received the turntable pronto, power supply package lost in Chicago USPS customs for well over two months. Had to purchase another power supply here in US, suddenly Australian power supply shows up, no notification, no tracking! I purchase items from Canada periodically, USPS shipping time all over the place, sometimes may get package shipped from same vendor in few day, other times up to two weeks.
USPS sucks for me, I always pay for upgrade service if item value more than $100. If I had one positive, never received damage package from them, only no package.