First off, congratulations on getting admitted to both Foster and Rotman!
The question, really, is what you want to do post-MBA, what you did pre-MBA (as this often matters) and where you want to work. Your choice should be guided by that.
For both schools, about 40% land jobs in consulting/finance/accounting. I'm sure the functions and roles will vary by location but I would look closely at the career stats for your desired industry/function/role. For that, I would also speak to a) alums who are working in those fields and b) current students going through recruiting for those fields. They would be able to give you a much better picture of what you can expect.
Do also keep in mind that the salary depends on the job as well. For Foster, 96% got jobs on the west (I would assume a LARGE number in Seattle). It goes as high as 145k and as low as 40k. Don't go by average statistics alone. Of course, TYPICALLY, the US pays more than Canada. There are exceptions and again, it all depends on your goals.
Good luck!