paulan

I have used eSIMs for a year now when I travel. Unfortunately all is not as rosy as this article makes it seem.

First on the Apple side: only the most recent iPhones can have more than 1 eSIM active so if you travel you need to choose whether your home network is an eSIM or a physical SIM. I have chosen to keep my home network a physical SIM but this makes it harder to find network providers who issue eSIMs.
Also, Apple has a number of odd deficiencies when you are using multiple SIMs. For example when you are travelling you usually want to initiate all calls from your travel SIM. However if you pick a Recent Call to phone back your iPhone will only use the network associated with the number that was called so it will use your home network to make the call and will not even give you an opportunity to choose your other SIM to make the call. This type of issue appears throughout the interface and while it may not matter with a work phone / personal phone scenario of using 2 lines, it matters a lot when you are travelling and trying to avoid silly roaming charges ( I am in Canada, the global home of silly roaming charges!)

Now to the carriers. Search for support of eSIMs in a country you would like to travel to: Europe, Africa, Asia.... You will find not only the mainstream carriers have limited eSIM support but they usually only support eSIMs for post-paid plans (12 month contract plans). If you are a traveller you want a prepaid plan and generally you get the best deals from MVNO operators. However these generally are the least likely to have any support for eSIMs. Plus, all of the ways of getting and transferring eSIMs in the article have to be supported by the carrier to work. So far the best I have found (even with the mainstream carriers in Canada) is to email you a QR code to install (or reinstall) the eSIM. Transferring from phone to phone; converting a physical SIM to an eSIM, etc you just won't find as supported: maybe in the ATT/Verizon world which I have not experienced. Also, they still like you charge you a fee for the QR codes, in Canada at least. So, from my perspective, any forcing of carriers to support eSIMs in Europe (and Canada) by Apple's new phones only supporting eSIMs will be good.

So, my experiences: I have used Orange's Holiday Europe successfully which gives you a French number that can be used throughout Europe with no roaming fees. It worked great for my wife and I in Italy. A bit pricy but you get the QR code via email which you can install before you travel and Orange has deals with the major country carriers. After a month you need to provide your identity documents (which you would have to do if you were getting a physical SIM in a store) and then the SIM will last for a year before expiring without use.

I have used Airalo to buy data only plans for Europe and the US. No issues to buy in advance and install and fairly cheap. This is the easiest if you only need data.

Fahfoofnik: The UK has been where it has been hard to find an eSIM so I have had to use a physical Lebara SIM which I got forwarded from a friend in the UK to Canada as you cannot get one except in the UK. However, as I am travelling to Ireland/England in a month I looked for eSIM providers again and found that LycaMobile is now supporting eSIMs so I bought one and was able to install it and activate it in Canada. Note however that their buying process still requires a UK address although they send you the eSIM QR code to your email. Who knows what, if anything, they will mail to my friend in the UK.

Last: make sure you understand how to set up the 2 SIMs on your phone or you may not get any of the cost savings from having a local SIM. Canadian carriers love to 'offer' their "roam like home" flat fee daily rates, but the problem with these is that any use of their SIM causes the daily flat fee to accrue: ie making just 1 text message would trigger the flat fee and cost CA$15 (and this goes to Apple's poor tools to manage multiple lines so it is not that hard to make a mistake). So I have had to call the Canadian carriers support to turn off flat fee roaming and switch to a-al-carte roaming and take the risk that I know what I am doing.

Finally, a small rant about iMessage. iMessage loves to drop your home cell number from being active in iMessage (in under 48 hours in my experience)) when the SIM is not active in a phone. This messes up all your iMessages that do not use your email address and it is not that uncommon for people to use just your cell phone number as your contact for iMessage as they don't understand it is not an SMS. So, you have to keep your home network active when you travel to not mess up iMessage even if you have a local data plan. If it were not for this I would likely just put my home SIM away for my travels and not try to keep 2 numbers alive when I travel. Note that WhatsApp does not do this even though it is tied to your phone number.