I'm at McGill currently as an International (U.S. citizen) student. It's...interesting. There are close to 30/35 of us this year as our class size was enormously increased (we have 159 med students this year compared to 130 the year above us). It is competitive...they recommend you don't apply if your GPA is below 3.5 and your MCATs below 30. McGill has a pretty good reputation with the oldschoolers out there (especially New England) so residency isn't a problem and as another poster said, as LCME accredited institutions Canadian grads are not considered FMG/IMGs. You have the same priority level (or however that's tactfully put) as U.S. grads for the Match. One of the great things about the Canadian system is b/c of how health care works here med students actually get to DO stuff. McGill meds do 18 months of class work, then go into the hospitals in January of their 2nd year and really get a lot of responsibility right away. Therefore, once in residency, they're wonderfully prepared to be doing stuff an intern does as they have been doing it for the past few years as a med student. McMaster also accepts 8 or so international students. Memorial in Newfoundland also accepts int'l students. Basically, as the other poster said, forget about the other ones as they are like a U.S. state school and won't take "out of state" (or international in this case) students. Actually...the same goes for McGill. There are more int'l students than out-of-province (not from Quebec) students.
Don't know much about the British system.