I've never had a problem getting into or out of Canada, but I've only traveled to Quebec a few times, not the other provinces. I usually travel to Europe, and since I'm a dual citizen I use the most convenient passport depending on if I'm a-going or a-coming. Cuts down on the hassles considerably. It also cuts down on costs. When I went to Brazil, I entered on my French passport to avoid having to get a visa that is required of US citizens (and costs $100 back then). I returned on my US passport, but I did have to show the airlines both.

When I moved to France (and back) I had my parrot with me. He's a threatened species and needed all sorts of paperwork having to do with international treaties. Going to France, they didn't blink, and I had to essentially beg them to stamp the paperwork. When I returned to the US, I failed to arrange for a vet to meet me at customs, so I had to wait for hours while the staff vet checked out all sorts of animals, including two racehorses who had just arrived from Argentina. When he got around to me, he took one look at my parrot, asked me if he was healthy, and sent me on my way. I don't think he was too keen on birds--more of a dog and cat kind of guy.

Once I was returning from Sarajevo in the late 90s with about five pounds of scrumptious dried lamb and beef that my host family had given me. I wrapped it up in foil and plastic and then in my clothes, but I was sure it would be discovered. But I got waived through at Newark with barely a nod.