Google Fi is not Google Fiber - it’s probably the least overtly scumbag-y of the US cellphone networks. That said, I switched away from it today after a few years of OK service because they don’t support Apple Watches.
> Unlimited 3G hot spot and $20/month for tablets with unlimited data can’t be beat.
It can if you spend a lot of time travelling - Google's data packages (on 4G!) are good in most of the world at no additional cost.
There's also a service aspect - Fi was often better where I am (downtown in a major US city) than T-Mobile (which my work phone is on).
That said, T-Mobile seems to be more customer-centric than AT&T - who even in 2020 seem hostile to doing business, and I'd consider them in future or for my iPad, just for further network diversity.
T-mobile’s standard plans include 3G roaming for data and calls(?) in Canada and Mexico and 2G data roaming in most other countries. You can also get a $5 “day pass” for 3G data and calls in most countries.
As an aside, their rate plans are all inclusive no extra taxes or fees.
It is an “extra charge”. Don’t you pay for every gigabyte of data that you use? It’s all bundled with T-Mobile. What’s the advantage of that over just getting another sim while you’re out of the country? Especially now with e-Sims being a thing.
They have two packages, one with per GB charging up to a cap and one bundled.
The advantage of using a primary plan (possibly augmented with local services from time to time) is that you have a stable phone number, and a lot less screwing about. For a casual traveler that may not matter. For someone who is in a different country every other week (pre-pandemic) it makes a substantial difference.