I turned a claim into the USPS last week. I'm just waiting for their denial and then of course the fight to try and get compensated for the damages THEY caused; through the insurance that I bought from them.
I had a plastic hard case damaged beyond repair by USPS Priority. I filed a claim online for the amount it would cost ($136) to replace with a new case. IN TWO WORKING DAYS a check for the full amount of the claim was in my mail box. No documentation of damages requested.
In the past I had a fishing rod damaged and filed the claim at the local PO. Took about 90 days for that one.
Just try and collect with UPS. They will have you jumping thru so many hoops you will probably give up out of frustration. If not, they often will claim item was improperly packaged. Marc