Don't give up that quick.. It's a small island: everybody knows everybody.. Put up the signs, use a radar gun and flag down heavy duty speeders. Check out licenses and registration... If everything is in order; ask for reduced speed in the future.. All of this can be done while the island is trying to move forward with laws to cover it. Yes, there will be people who don't care because there are no laws... ok; talk to employer if driving on the job. It's a lot better than just saying nothing can be done.