The Hobie spin and jib simply do not work. Sure, you add sail area but the spinnaker throws wind right back into the mainsail and is just wasted. THe pole is definitely too short.
When racing you will take a pretty good hit for the spinnaker and for the jib, and neither one of them make the boat sailing significantly faster.., certainly not to the modified number.
Whereas the Hooter systems makes the boat sail faster then the number.., that is why I have had so much success and won so many races with it.
In either case you need the spreader bar that we and Hobie sell for the bows.
Good luck,
Rick