that is what I was also thinking. I think I will go for 46 Maui Ultra Slalom Race, which has a relative lagre area for its length, (an 46 is equivalent to 48/50 normal slalom fin shape).
with respect to Tuttle vs. depe Tuttle I was also surprised to see there just a Tuttle box. As the board is originally equipped with a 50 cm Drake Venom, I would hope the Tuttel box will be abel handle it. Also I couldn't find any reports about such breakages on the Futura.
Can someboy from SB can comment in this please?