Driving from BC to ontario?

If you were going to southern Ontario then, yes, it would be faster to go through the States than to follow the TCH and go around the Great Lakes. Since you're going to northern Ontario, it would most likely be faster to stick to the TCH. Go to Google Maps (see link below), click on "get directions" and type in your starting and end points. You'll get a map showing you the best driving route along with distances and times. This should help you decide.