I am in the US, and I had some interest from a buyer in Canada for a pair of shoes. She asked me to relist (if there weren't any bids) and if I would mail the shoes directly via usps instead of opting into the Global shipping program. My listing was set with flat price for shipping ($4.95) when I was opted into the program. She mentioned something like $30 extra in charges via the program. I changed my listing to allow US and CA and opted out of the program, but I also switched to calculated shipping. When I researched the rates through the usps website it looked pretty awful for a 1-2 lb package. Is it actually still better to ship directly? Also how do all the customs related charges work without the program? Thanks for any input you can offer!