USPS Priority Mail

What do you think about using USPS Priority Mail to ship two 50 pound boxes (double boxed, 35 pound speakers) across the country?
One thing about UPS..If using them make sure you have it boxed or prepared for shipping by authorized UPS agent..We ship larger antiques all over and the last time UPS destoyed an item they refused the insurance claim because it wasnt packed by them...It will cost you more but( not if, but when) something is damaged its all on them..
Based on my experience, US Post Office is the best! During the winter we had unusual and harsh snow storms in Seattle. I was awaiting shipments from UPS and the Post Office. In the snow, my 50 lb box was deliviered by the Post Office. It was not held at all.

I never received my delivery from UPS, even though their systerm showed it was "Out for Delivery". After three days of frantic phone calls, they finally said their system showed "Out for delivery" in error. They explained that they could not deliver because my road was "too unsafe", yet the Poast Office delivered under more treacherous circumstances. I was not able to pick it up at theuir distribustion center, because it was "already loaded" on tehir truck. Then they admitted that they could not locate a $6000.00 declared value box. Two weeks later it was delivered. From now on I support USPS 100%.
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Commcat-I know tandem dump trucks dump their loads but have never seen a USPS trailer dump a load. Maybe I live in a different part of the country? I used to drive for a USPS contractor & everything was loaded into a cart that was wheeled on/off the trailer.

Tvad-Depending on what time of the year it is & how far away the destination determines whether the package will fly or not via Priority. There is no guarantee for 2-3 day delivery. They will *try* and deliver in 2 or 3 days.

Speaking of flying, that is the best way to ship something. Ground packages get put on the conveyor belt & get handled many more times than air packages.

Regardless, always pack your gear to survive, at minimum, a chest high drop. If you don't feel your package is secure enough to survive a chest high drop, don't ship ground or rethink your packaging.