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Original Post
You state: "First Class mail is probably the least pricey shipping method for the majority of packages that weigh less than 2 lbs." This is incorrect. First class mail is available for packages weighing from 1 ounce to 13 ounces ONLY. For packages that weigh no more than 13 ounces and quality for first class mail, THERE IS NO ALTERNATIVE SHIPPING METHOD THAT COMES CLOSE TO THE LOW COST OF USPS.
After about 25,000 ebay sales, I've refined my domestic choices BASED ON PRICE:
Up to 13 ounces - USPS first class
13 ounces to 3 pounds - USPS parcel post
Over 3 pounds - Fedex
There are 2 exceptions to these being the least expensive choices.
1. USPS parcel post is sometimes less expensive than Fedex if the destination is very close to my location.
2. USPS parcel post can be less expensive than Fedex to rural locations because Fedex imposes a home delivery charge and a separate delivery area charge for locations that are far from their depots.
Even with the Paypal discount for UPS, Fedex is less expensive than UPS for every calculation I've checked from my location.
I do not use more expensive classes of mail unless customers specifically ask for them. Priority mail can be ridiculously expensive for heavy packages to distant locations. And the delivery time for first class mail to most US locations is 3 days (just slightly more than for priority mail).
NOTE: You said "For guaranteed delivery within two to three business days, USPS Priority (up to 70 lbs.) is a darn good value." This statement is misleading. USPS does not "guarantee" that priority mail will be delivered within their delivery goals. If they miss their delivery goal, all you get is an apology from a window clerk.
After about 25,000 ebay sales, I've refined my domestic choices BASED ON PRICE:
Up to 13 ounces - USPS first class
13 ounces to 3 pounds - USPS parcel post
Over 3 pounds - Fedex
There are 2 exceptions to these being the least expensive choices.
1. USPS parcel post is sometimes less expensive than Fedex if the destination is very close to my location.
2. USPS parcel post can be less expensive than Fedex to rural locations because Fedex imposes a home delivery charge and a separate delivery area charge for locations that are far from their depots.
Even with the Paypal discount for UPS, Fedex is less expensive than UPS for every calculation I've checked from my location.
I do not use more expensive classes of mail unless customers specifically ask for them. Priority mail can be ridiculously expensive for heavy packages to distant locations. And the delivery time for first class mail to most US locations is 3 days (just slightly more than for priority mail).
NOTE: You said "For guaranteed delivery within two to three business days, USPS Priority (up to 70 lbs.) is a darn good value." This statement is misleading. USPS does not "guarantee" that priority mail will be delivered within their delivery goals. If they miss their delivery goal, all you get is an apology from a window clerk.