This completes a year of using Google Fi for cell service. Fi is a meta-provider which uses both Sprint and T-Mobile for underlying cell service. The downside is that you must buy a phone from Google, and there are only 3 options. They are very nice options, though, if you don't need an iPhone.
(Other perks: they bill automatically; they charge you $20 for base phone service and $10 per GB of data; they properly fractionate that down to a unit of 10 MB.
They include a thing called Google Assistant, which looks for wifi networks in your area, and connects to them if it recognizes them. Then - this is key - it sets up a VPN back to Google, because it doesn't trust the generic wifi network. If you don't have a VPN service, this is pretty good. It coexists with other VPN services, too. I have one for work and one for home.
The total cost included $700 for the top-end phone, plus an average monthly cost of 31.50, for a total of $1078.
I have good wifi at home (I should know, I maintain it) and at the office (I should know, I maintain it). Fi is happy to switch to wifi for calls and data, so I basically only consume billable data while in transit or otherwise travelling. If you are out on the road all the time, this may not make sense for you.
The cost of my Sprint service in 2015 was $1054, but that does not include the cost of the phone, which was an additional $300, spread over two years. I wrote about Sprint previously
I'm planning on keeping Fi service, and in the next year I expect the bill to look much like this year's -- which is to say I'll pay about $380 for the year of service, and nothing new for the phone.
For two years of service and the hardware cost:
Sprint: $300 + $1054 + $1054 = $2408
Fi: $700 + $380 + $380 = $1460
Looks like a pretty good deal. I recommend it.