I've had over 100 guitars shipped to me via USPS from the US and never had a problem. They won't insure for more than $1000 though so you have to weigh your options there. UPS and Fedex only charge the brokerage fee's if it's shipped ground, if it is shipped Express the brokerage is included in the price of shipping, however, this does jack the shipping charges. UPS or Fedex ground from the US to Canada CAN actually take as much as 18 days. Their claim of 7 days is 7 business days not counting whatever time it takes in customs, when they are really late they just blame customs. So, if you are concerned about time and such, Fedex express is the best way to go. You will pay GST, PST, and HST (if your province has them all) when it enters, so whatever the total amount of tax you normally pay is, you'll have to pay that based on the declared value of the shipment.
For what it's worth, USPS has never lost or damaged an item on me, Fedex and UPS ground have both damaged items and refused to pay the claim. Fedex and UPS express are both good although I think Fedex is tops.
Jeremy
PS. UPS brokerage fee is I believe 6% of the value with a minimum of $35. So on a $1000 item you'll pay $60 more for the brokerage. In BC here, we have 7% GST, and 7% PST so in total 20% if shipped UPS, an extra $200 hurts
