I have used the AT&T $100 plan on several cruises and have had great success with making and receiving calls and texts. Knowing that their included data is very minimal, I’m reluctant to use it. It seems you could go through that data very quickly and end up with a big data bill at the end of the cruise. For this reason, I also purchase the Carnival WiFi Value plan to cover my data. The combination of both of these plans work great and the cost is worth it to me. I use the $10 AT&T International Day Pass while in port.