[skidmarks]

As far as the USPS goes. I had a couple smaller packages in plain cardboard with priority postage take 15 days to deliver, but shipped a few the same day in flat rate USPS boxes and they got there either ontime or 1 day late.
To me, looks like the flatrate boxes take Priority over anything else.
One piece, that went less then 100 miles from me took 14 days ??

Smaller stuff the padded flatrate envelope is the quickest and for the difference in cost is a better choice. Most people are patient but some flip out if its 1 minute late