I've used the Starbilizer side fins quite a few fimes in the past.
They work pretty well,
I hope you have been able to seal up the leaking screw.
Not sure why you feel the Starbilizer side fin inserts are problem.
If you dinged the board enough to open up one of the side fin insert
screw holes, it seems likely that the same ding would have penetrated
the TufSkin on the rail if the side fin hole was not there.....right?
The side fins and the mounting inserts in the board make the GO a little more
attractive to families with kids or others to teach.
Hope this helps,