I used Airalo twice. It was OK, but the plans expire after 30 days along with any unused data. I had 2 trips to the US with a few weeks gap in between, so had to buy 2 separate plans. Last year I tried Roamless with a 20GB global non-expiring plan. There was a deal where they threw in the same amount of data on a 30-day expiring plan free, and it's smart enough to use the expiring plan first before dipping into the non-expiring. It's been about a year and I still have a balance after using it in US three times, Bermuda, and Italy last year, and will be using it in the US, Italy, Greece, and Turkiye this year.