Someone who has ordered something from the US can you tell me your experiences with USPS?

I have purchased a Line 6 UX2 interface on Ebay and got it shipped on the same day by USPS First class on November 13th US Time, The interface has went through a sort facility in Boston which has been dispatched from there on the 14th after being received on the 13th. the package then went through Lawrence, MA sorting facility on the 15th, and dispatched on the same day.

The item has went through a couple of sort facilities like Jamaica, NY and then ISC New York which then said it was dispatched ( ICS New York is a sort facility at the airport) you would expect the item to be sent from there straight away to New Zealand, that was on the 18th of November US time, Today I checked my tracking number patiently waiting for the interface everyday it kind of annoyed me, it has taken them around 2 weeks to move the interface form the Airport sort facility into Opa Locka which is around 1000km from the Airport sor facility.

Today it has departed the sort facility, if you have had previous experience with USPS have you had this problem before? I'm actually annoyed at this since I've paid a fair amount for the shipping hoping it will come in at least a month max. now I see that it will take a bit longer... do you think it will come this month, or at least in the next week? Thanks for your help :)