On the glass boat toughness question, I used to have a clackacraft, have a Lavro now. Either boat could take a dead on sideways hit on the chine without fazing it. I've lost some gel coat in places, but have never had damage that actually affected the integrity of the boat.

I do know a guy who had a sharp stick punch through the side of his glass boat, but that's a different story. The only reason I worry about hitting a rock is that it might scare the fish.

Both of these boats were easy rowers. However, The aluminums I've rowed have always been comparable, so I agree with the other guy, I think you should look at how the boat is balanced.