Whats the difference between USPS Priority Mail International and First Class Mail international ?

Here's what I already know

USPS Priority Mail International - US $29.75

USPS First Class Mail International - US $12.89

-So how long will it take to choose from either of the above to ship something in a flatrate envelope from USA to Philippines???


P.S I have tried USPS EXPRESS MAIL INTERNATIONAL wherein I bought something from ebay from USA to Philippines (It took 7 days instead of just 3-5 days). Besides the crappy and late tracking system and most of all NOT TRUE (It says attempted delivery even though there was no attempt at all) which i already know, my followup question is , Doesnt USPS EXPRESS MAIL INTERNATIONAL still deliver door to door? How come in my country it didnt? Or is it because our Postal Service just sucks which I believe it is.



I appreciate the help guys , peace


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