Traveling to Europe and have been using a Orange Flex E-Sim, which is incredible value for a short trip.
I downloaded the app and selected the highest plan and entered the FLEX code before payment to reduce charge to PLN 1.00 (AUD 0.32 at current spot rate) for the first month. It comes with 11.14 GB of EU roaming data. I am still using the service but assume I will need to terminate the plan before the next month commences to avoid being charged for an additional month. I am currently in Greece and Orange will use whichever of the three local carriers is strongest, which is great when in more rural areas (including 5G!).
Ongoing cost if you need additional months is PLN 80.00 (AUD 25.97 at current spot rate), which is still great value.
Also, app interface is great and it’s very easy to add the E-Sim to your device. If you use all the EU data within the month you can add additional data for PLN 12.00 (AUD 3.90 at current spot rate) per GB.
It says you can add additional sims for other devices to share the data, however this doesn’t work for EU roaming data, only Poland data.
You need an ID to verify. I tried a drivers license, which didn’t work. Aussie passport worked. It’s automated- you scan the passport with the camera and then take a photo of yourself.
I am using iPhone 13, so have my Boost physical sim active alongside the Orange E-Sim. This means my Boost service will use the cellular data from my Orange service to make WiFi calling to Aussie numbers as if I am still in Aus. Note that Telstra are smart and will block you from calling European numbers when WiFi calling from overseas (even when those minutes are included in your plan). What you can do is use the included minutes on the Orange SIM to make intra-European calls (very intuitive to do on iPhone, not sure about android).
Posting this from a beach in Greece so excuse typos…