Here is a posting I placed on another airsoft forum:
UPS is the most expensive shipper. Not only do you have to pay the shipping but there is a brokerage fee, tax, & customs for an additional 21%
Fedex isn’t far behind at about 12%
USPS, I have only been charged about 5% in the last 5 years if anything
Another thing to note is that if you do ship through USPS, the items would be delivered through Canada Post and you would still kind of be still supporting a Canadian business.
UPS delivers typically until 9pm and sometimes just scan the item delivered
Fedex deliveries until approx 8pm and if you have to pick up the item you must travel far South East
USPS/Canada Post delivers until 8pm and if the item does not fit it would be at a post office close to your house or if small enough be left in you community mail box.
On a final note, USPS tracking numbers starting with a LK are not tracked within Canada and make it very difficult to locate your items. I find it worth while to pay a bit more to have a fully traceable item.