The route I followed on the way back was the exact Hairshirt route there, which was pretty easy going - there is some uphills on gravel, which is where you come off King St/St. Paul St onto .. 19th St after St. Catherines. Then there's a slight incline or two (rolling hills, nothing at all too bad, though) on Fly Road. Coming up towards the escarpment on 11th St/50 Rd. had a few inclines, but then there's the insanely steep downhill (which I came up on the way, too). I was there at 10pm and didn't have enough lighting to feel safe, but I was having no trouble at all holding a comfortable 50km/h on the brakes down there. At the bottom of this hill there's a small side road with a field of pear trees on the eastern side. Right on that edge there are a couple of cherry trees - sample them if you pass this place, they are the best cherries I've ever had.

Hills don't show up much on Lakeshore, and coming through Mississauga you get a few up/downs as you would on say, Queen - but I don't recall anything super nasty - it's like riding Bloor, there's up/downs and nice flat sections too.

Edit: Forgot about the hills leaving the falls, going up Niagara Parkway - there are a couple of steepish up/downs, it does level out after you get to the Adam Beck generator place if I remember right.

I can't vouch for how the hairshirt-there route is, as we did our own thing going.

Here's the full hairshirt route:

http://www.mapmyride.com/ride/canada...auga/532959205

Hope that helps.