I use OTB Abyss boots as my primary 3 season wet boot.  I have a couple pairs of Keen sandals (H2's) that I use for my camp shoe for much the same reasons as you've stated.  I love them and they are definitely sturdy enough and have enough support to function over portages as need be.  In fact when I'm in Algonquin where the ports tend to be fairly well groomed I pretty much wear my Keens all the time.  I think you'll be happy with your choice.

By the way, if you look around, I'm sure you can find them at a better price, for example,   (You need to Login or Register and   (You need to Login or Register.