Here is the difference in my opinion.

Recently bought a 2004 Marzocchi Marathon S ($275USD) from speedgoat.com . USPS Air shipping $16.25USD. No Duty. Total $291.75 US = Crazy Deal.

Recently bought 4 tubes, some alloy bolts and a seat clamp ($50USD) from cambriabike. UPS shipping $15.00USD. Duty and brokerage $40 CDN. Total Around $100 US = Am I really this dumb? (Estimates only. I lost receipt.)

In it's defence Cambria does offer USPS shipping to Canada on low value small orders, but only by phone, so I didn't hassle it. I'm not paying to sit on the phone.

The UPS depot at Keele and Finch in Toronto is a joke. Six broads gabbing behind the corner, pumping Flow93.5 while one "serves" the customer. Took 10 minutes to grab the package. UPS sucks.