Best Triathlon?

Just wondering about the best tri to compete in, in terms of atmosphere and excitement. I live in Bermuda, and there are some triathlons here (mainly sprints) but they only attract about 50-60 competitors. There was the Escape to Bermuda Olympic tri last year, which was an international race, but even that only had about 150 competitors. And they've cancelled it this year, due to lack of funding

I would really like to do a big event, where there are lots of competitors and spectators, and you can really soak up the atmosphere. I'm only really up to Olys or Sprints at the moment, so the ones I'm considering are New York, London, or Chicago. Has anyone competed in these, and what are they like?