That's incorrect. There are 2 6s models sold in the usa,and they have very similar but not identical radios. For example a Verizon 6s doesn't contain ALL the radios that the att 6s has,although it has most. The Verizon model is a subset of the att model,radio wise.
With regards to the 5s,yes there are more models but the att, tmobile, and Verizon models are the same model number. An att 5s on Verizon would work just as well as a Verizon 5s,and vice versa. Now there are 5s models that won't work on Verizon or tmobile and att...
Dpham is correct, but you are still going to want to look at the entire picture before making a decision.
At this point, the A1633 (6S) and A1634 (6S+) are the most comprehensive when it comes down to the number of radio bands supported. You can get them from AT&T--locked to AT&T--or directly from Apple--Unlocked
All those poor schmucks on Sprint, Verizon, and even Tmobile are stuck with the A1688 (6S) or A1687 (6S+). The only difference between all of the devices is ONE Radio Band--support, or lack of, for Band 30
PSA: Apple’s iPhone 6s CDMA spec change makes AT&T’s model its best worldphone | 9to5Mac
Last year, the Verizon Iphone 6/6+ and the AT&T 6/6+ both used the same model #s A1522 and A1549 and were identical from a GSM/LTE perspective EXCEPT the Verizon version supported CDMA.
However, if you were looking for the model with the most comprehensive radio bands, you had to go to SPRINT or buy direct from Apple and get the A1586 or A1524.
Both of those models support bands 38, 39, 40, and 41. Not really a big deal in the US, since Sprint is the only one that uses them, if I recall correctly, for their High Speed "Spark" LTE.
Prior to this year, Sprint was a real hard *** when it came to unlocking phones, so, if you didn't want to buy from Apple or deal with Sprint, you could buy an already unlocked Verizon A1522 or A1549 and be perfectly fine.
Now a couple of observations:
1) None of the Iphone 6 (or even 5S models) from any carrier or Apple directly support Band 30
2) If you are "lucky" enough to be on Sprint, their Spark LTE can be extremely fast, but if your phone doesn't support bands 38, 39, 40, 41 and you are not fortunate enough to be on Sprint, you have nothing to be upset about.
I recently sold a Sprint Iphone 6S+ and listed it as being unlocked and compatible with Sprint, Verizon, TMobile, and AT&T. It was an A1687 not an A1634. I disclosed that information to the eventual buyer and they were happy, and of course, it didn't support Band 30. However, it was just as compatible with AT&T as the Iphone 5S and Iphone 6, since they don't support Band 30 either.
WTS: Iphone 6S Plus 64 GB Rose Gold Unlocked - iPhone, iPad, iPod Forums at iMore.com
Obviously, if price and availability is completely equal, make sure you run out and get the phone that supports Band 30, but, since most AT&T customers probably lack support for Band 30, I can assume it isn't a huge issue.
If you can save money and.or aggravation, get the 6S Unlocked from any other carrier, besides AT&T and don't worry.
Apple iPhone Specs (All iPhone Models) @ EveryiPhone.com
By the time band 30 gets to be a critical requirement, most people will probably have new phones.
I am hoping one of the carriers deploys service on Band 69, so I can run out and buy THAT phone. Then I can tell everyone that my phone supports Band 69, and am showing my support for the manufacturer that believes 69 is an integral part of the American cellular experience.
Even if Band 69 is only good for those lucky enough to live in an underground bunker in Roswell, New Mexico, my phone will be locked and loaded. However, I'll still keep my other non-banded 69 phones around for kicks.
My apologies for the outside linkage, but I wanted people to have easy access anything dealing with Apple and radio bands. It can be really hard to keep everything straight.
The marketplace listing is already closed and sold and I'm not trying to self-promote, but I thought the pictures may be beneficial to some.
As someone that has both Verizon and Sprint, I consider myself a double-schmuck. If AT&T happens to do something truly magical with Band 30, I may become a triple schmuck, but until that happens I'll be content to use whatever Iphone 6S I can get quick and cheap.