Some Airalo feedback on OzBargain (may have to go through a few posts to get the answers you're after) 
Airalo Deals, Coupons & Vouchers - OzBargain

 I went to Sunshine coast in July, I used https://www.getnomad.app/ you can download their app and purchase/cancel through. Worked as it should was on vodafone au network. You set it up before your travel, then activate it once you land. Would use again. 

Also disccussed here

https://www.geekzone.co.nz/forums.asp?forumid=179&topicid=306982

My son recently did a trip to Europe and set up an Esim with (I think) Truphone in advance.  All worked perfectly and was a lot less expensive than using NZ carrier roaming options

The rates seem quite similar between the various travel sim providers, I think you just need to get the best deal for your planned trip

I've used Airalo in Europe for 2 trips. 

Seems to need internet connection to activate so both times I resorted to the free wifi at the destination airport.

Occasionally (<5% of time?) speed dropped to something like dial up for no obvious reason. Overall would use it again.

If you use the referral code PAUL2833 we each get a princely $US3 credit.

I used Holafly in Europe for four weeks recently.  Was excellent and far better than Airalo which we used in the USA at Christmas. 

paulchinnz:

I've used Airalo in Europe for 2 trips. 

Seems to need internet connection to activate so both times I resorted to the free wifi at the destination airport.

Occasionally (<5% of time?) speed dropped to something like dial up for no obvious reason. Overall would use it again.

If you use the referral code PAUL2833 we each get a princely $US3 credit.

Be careful about early activation - rule may vary depending on network:

Eva888: I understand the data component, but can someone explain what if you have 2FA for banking apps or Wise or some other app sends an authentication text. With roaming with my NZ provider they are sent to my NZ phone number while I am overseas.

Does installing e-sim mean I don’t need NZ roaming and the authentication texts are still received by my phone via the e-sim? -A travel esim is a different number to your regular number  

If someone in NZ calls me on my NZ mobile number while I am travelling, do I still get the call with an e-sim loaded and there is no other charge? if you have wifi calling on you will receive calls/txts if you are on data - you just turn off roaming for your nz roaming and have all your data come through the travel esim. 

Does e-sim work if you are on a ship in the middle of the ocean? no - it still uses cell towers for connection.

Recently returned from a trip to UK, Europe and Egypt - used Ubigi installed eSIM and app, and found it worked really well everywhere we went. When I researched beforehand the main difference between Ubigi and Airalo is that with Ubigi you install a single eSIM that works everywhere, and when you land somewhere you can connect via the eSIM to whatevever network Ubigi supports in that country using the app to buy the data pack that suits best for your needs. You can install Ubigi and download an eSIM for free while you're still in NZ, and check it's going to work on your phone (they offer data plans for travellers coming to NZ too).

Some plans are cheaper than the equivalent on Airalo (eg. 10GB in UK for 30 days is USD12 on Ubigi, USD22.50 on Airalo), and some seem a bit mpre expensive, but the convenience factor to be able to set up and top up from anywhere (without requiring WiFi) is great.

razor2000nz:

 

Eva888: I understand the data component, but can someone explain what if you have 2FA for banking apps or Wise or some other app sends an authentication text. With roaming with my NZ provider they are sent to my NZ phone number while I am overseas.

Does installing e-sim mean I don’t need NZ roaming and the authentication texts are still received by my phone via the e-sim? -A travel esim is a different number to your regular number  

If someone in NZ calls me on my NZ mobile number while I am travelling, do I still get the call with an e-sim loaded and there is no other charge? if you have wifi calling on you will receive calls/txts if you are on data - you just turn off roaming for your nz roaming and have all your data come through the travel esim. 

Does e-sim work if you are on a ship in the middle of the ocean? no - it still uses cell towers for connection.

  

 

The missing part of this post - most phones only support one ESIM and one SIM - so if your regular carrier is an ESIM, the travel ESIM overwrites it, and you aren't roaming on your regular carrier. In this case, your 0FA (I refuse to call SMS 2FA) just disappears into the aether. If the carrier profile is not on your device, you don't have wifi anything, calls or texts. If you overwrite your ESIM, then the carrier profile is gone - your device does not even know to attempt to wifi connect to your home network (for obvious reasons).

ESIMs can also work in the middle of the ocean - cruise liners tend to have access to satellite cellular networks - but you don't want to know what the roaming charges are on Inmarsat.