I've worked in fajardo and had no issues with internet. I'm in the USVI, in St. Thomas, and despite a very unreliable power gird, I've no serious issues working as most spots have a generator. There is almost no tech scene here but the tax advantages are serious! Some financial companies take advantage of it, but I don't know of anything in tech.

It's an awesome spot for working remotely if you're into the water.