Some people claim Canadian medical schools are all the same, and I don't think it's true. Yes social supports can be a big factor, especially if you are still relatively dependent on your parents/relatives. Location can be a consideration too but I think it's very important to consider the curriculum structure and educational doctrine of the school itself.
1. I think it's important to look at how many weeks of electives you would get at each of your options, because there is huge variation between schools. Also look at how many of those elective weeks are pre-Carms. This can directly affect your ability to match to your preferred specialty, and your ability to be competitive in more than one specialty under the new elective cap rules.
2. If you are considering a career in surgery or radiology, or you (like many doctors) consider anatomy to be the cornerstone of medicine, get the details of how the anatomy curriculum is taught and structured at each of your options. Find out which of your options teaches anatomy on actual cadavers. Some medical schools just teach anatomy once to a pretty basic level at the beginning of first year and then never touch/test it again, while others place a strong emphasis on anatomy in every unit of preclerkship. In other words, some medical schools seem to value and emphasize anatomy education far more than others. Find a school that values anatomy education as much (or as little) as you value anatomy education.
3. Find out how many students are failed and have to repeat a year at each of your options. You may be surprised at the differences between schools. This is not something you want to have hanging over your head while you are trying to learn medicine.
4. Find out which of your options grade their students against an absolute standard, and which of your options grade students against each other. Do you really want to be competing with your classmates for a pass?
5. Find out how much of the curriculum is mandatory case-based or small-group learning sessions and mandatory clinical skills sessions at each of your options, and whether these are graded on participation or ungraded. Some people really enjoy learning this way, and some people really don't. Some people really enjoy spending lots of time in small-medium groups with their classmates, and some people really don't. Which one are you? Make sure you find out the total hours divided by term length, not just "a typical week" because the "typical week" may be misleading about the actual amount of this mandatory small group and clinical skills stuff when taking into account the very heavy weeks.
Canadian medical schools are not all the same.