I think what he meant Paul was the 30 sized might not hold up to the extra stress. I had the same thoughts too on a conversion, but he filled me in on the recommendation of the 46. Looks like they are rigorously testing new equipment daily. Stephan has really done his homework. :

The 50 looks great we talked about it on the phone, my mouths watering over the 70. I just need to buy a motor and purchase the kit. I might go for the 60.