Yeah I usually just ignore anecdotal evidence and am probably gonna do the same here since it's, you know, anecdotal. Studies on the matter show that the USPS is extremely efficient (best public postal service in the world by some measures), and FedEx and UPS will often USPS because of this efficiency (true story - crazy right?).
And the US government does a lot of things right man. Big institutions always have built in problems, be they government or private.