I know people that have lived in Hawaii and they say that after you finish seeing everything there is to see you're essentially just trapped on a small island. I lived in France and even if you get tired of your surroundings public transportation is so good in Europe that you can easily go visit a different country every time you have a long weekend from school. Just a thought.
Just keep in mind that London is much colder and has lots more precipitation, but Hawaii is very small and going anywhere else, like for vacation, is very much out of the question. As for the people, you'll most likely feel more comfortable with English people. They have a more similar culture. Hawaii is a bit more native feeling, and the communities are smaller. Good luck
We know nothing about your or your preferences and therefore can not help you decide. It is unlikely that you even have a job waiting for you once you leave school and if you do, it is unlikely to be in Hawaii making your so called choice obvious. London.
I think London because it is much bigger and there is so much adventure and opportunity there. Hawaii is great but after a while you been everywhere and done everything there. So I say London.
