Jazzgal, I didn't use the WIFI calling, but my son just did in Aruba without any problems.

Most places have WIFI, so it isn't a problem unless, like Carol said, you are on the road
and need to make an emergency call.

If I remember right, there was another member who used it all the time, without a problem, and that is why
I posted it. He was very happy with it.

I have an unlocked smart phone, so I sent away for a SIM, in April, and that worked great.
I was concerned that after Irma the WIFI wasn't going to be reliable, but we never lost it.