Planet13 - 7:26 pm on Aug 6, 2013 (gmt 0)
I've been pretty lucky with USPS.
My main problem is when someone wants a ship to address that USPS DOESN'T deliver to and picks US mail instead of the more expensive UPS Ground. Then I have to deal with having to charge them more dollars because USPS won't deliver there.
I have probably had a few more bad experiences with USPS than with UPS / FedEx / DHL, but I use USPS about 97% of the time (not an exaggeration).