This is great news. The USPS is hands down the best shipping provider. Priority Mail, especially the Flat Rate boxes, are often the cheapest and fastest way to ship packages.
One of my favorites is the recommended carrier of Monoprice, Norcon, that emails you a photo of the delivered package once delivered.
Ontrac is a west coast delivery service, and from what I can tell they keep prices low by using mid-90s beater white minivans with a company logo magnet and issuing their employees a polo T uniform.