I want to know the difference in size of the 6 hp yamaha compared to the 5hp honda. It's mainly the dimension of the engine top and shaft length (presume they are the same shaft length).
There doesn't seem to be any Honda branded carry case so was looking at the one sold by Yamaha main reason for asking about the size of each OB.
If its something you are serious about buying why not head to your nearest dealer with a tape measure and negotiate a deal. With two such good choices it would come down to customer service and price as much as anything else.