I have a sit on top kayak with a 50# doodle.  He is 2 years old and far too much energy to keep us reasonable stable.  I have the benefit of being in a house and planning to find a canoe this spring.  My sit on top had a section behind the seat that I thought would be perfect for him.  Bought when he was a puppy.  It didnt work.  He likes his people too much.  Especially when they are nervous....make sure they can be in front of you.  And yes, the blow up is tougher in wake and wind, but find one that is as rigid as possible when inflated, the reduce drag.  Higher quality usually does this.