In my famliy we had 3 2006 starboards, together with my friends we used 5 starboards from 2006 with tuttlebox. models:
3 Isonics
2 s-type
On 4 starboardswe saw several cracks around the finbox. But we never did repair it. I only made it flat, so I wouldn't have any rough surface in scoop/rockerline. A very
proffesional boardrepair shop in the Netherlands told us that the
Hard-foam used around the finbox is waterproof, so repairs would be expensive & unnessecary.
On another board a
JP freerace we experienced with a
select fin RS7, which was like 10 times more powerful than the standardfin (eventhough the select was 5cm shorter!?!

)that
complete finbox including hardfoam
seperated from the boardcore. After that we heard
everytime when sailing that
hit a gust a CRACK #!$3^&*(*&%^, That finbox was completely replaced by a new tuttlebox.