[geoff's two cents]

Both on Main.

The primary reasons would be that Main is the street most in need of a boost, and it has the most lanes for the longest stretch. Main is also closer to the GO station.

I'm not in favor of having one on King and one on Main, as King goes down to two lanes through the international village, the city has no intent of running LRT through Westdale, and because transit is easiest to use when both directions run on the same street.

With the latter reason in mind, it wouldn't be a big deal downtown, but the distance between Main and King is considerably wider at Dundurn, and somewhat ridiculously so on the west side of the 403. This wouldn't matter for myself, but it would make transit less user-friendly for the elderly, the handicapped, etc., who would be less inclined to walk for such distances in inclement weather. Without LRT on King, the street could still be served by non-rapid bus service.

The only major problem with this is the fact that Main would have two less lanes (three, if the city did the logical thing and widened the sidewalks), which - again - brings up the issue of two-way conversion for Main and King, and the whole nasty bunch of problems that go along with that - I'm thinking primarily of the 403 interchanges. In a perfect world, we would either be able to do those conversions, or the city would run LRT between King and Main (George), and go underground at Bay. This would, however, mean buying up property all along the line, demolishing part of the Fortino's plaza, constructing a new bridge across the 403, etc.

In my opinion, that is the only (!) serious difficulty with avoiding the King and Main separation - but having the east and west lines separated by such a distance would make the city's LRT something of a laughing stock among Canada's major cities.

The city has made so many enormous mistakes in the last half century - LRT is something it should definitely do right.