At the risk of sounding like I'm jumping on the bandwagon, I will simply say that I have mailed a LOT of audio gear and LP's by USPS during the past 4 years, and have not had a single problem. Priority Mail gets there fast, you can trace its movement using the USPS web site, and the insurance charges are reasonable. The USPS has made a real effort in recent years to become competitive with the commercial shippers, and they have largely won my business. It's also nice that I have a post office about 0.5 miles from my house, whereas the FedEx and UPS offices are a 20-minute drive.
Kudos, indeed, to the USPS.
Kudos, indeed, to the USPS.