Our Waterfront Trail is pretty awesome. I'll ride as far east as Ashbridges Bay Park and as far west as Rattray Marsh Conservation Area. The Waterfront Trail actually runs from Niagara-on-the-Lake to Brockville, but I primarily use it in Toronto and Mississauga.
Most of the trail in Toronto and Mississauga is off-road and paved, which is ideal, but some parts are on quiet streets. I don't mind that at all, but there's one stretch that's far less than ideal. This is a stretch in Mimico / New Toronto from Norris Crescent to First Street.
Between Norris Crescent to the east and First Street to the west, the Waterfront Trail forces cyclists onto Lake Shore Blvd W. This is where Sue Trainor was struck by a car and killed last summer, and where I took my hardest fall while crossing streetcar tracks.
I don't know if the Pan Am Path will address this stretch, but something needs to be done. Toronto cyclists deserve better from our Waterfront Trail.