If your looking to send a package Priority mail, please be aware that USPS does not stand behind or guarantee their priority mail service. USPS only guarantees Priority Express packages, so why pay that priority price that they keep raising, and risk them loosing your 2 day package.
If your package is not delivered in the two day time frame USPS can’t even tell you where your package is, or when if ever, it will be delivered.
USPS gives you a tracking number but it’s not worth the paper it’s printed on. The information is not updated with the current package location or expected delivery date, and if it gets lost, they may never find it or even know it’s missing, because no one knows it’s location. So don’t take the risk and send your important packages this way!
With UPS and FedEx the receiver receives their package in the slotted amount of time, with current location and delivery date updates. They also have the same options such as flat rate shipping, free shipping supplies and scheduled pickups.