[X 2014 General] cb474:
In response to some of the things people discuss above. I emailed the author of the AnandTech review to see if he knew more about what's going on with these different variants. He said the information published in the AnandTech review came from the "reviewer's guide" provided (I assume) by Motorola. So that probably makes it the most credible information currently available.

According to that guide, he said it appears there are four variants received for testing by the FCC, using a naming system different from what is used in the most of the posts here. Those variants, as indicated in the review, are: IHDT56QA1, IHDT56QA2, IHDT56QA3, and IHDT56QA4. You can see they only differ by the last number.

So those appear to be the actual different variants. Motorola has also used the XT109x model number system. At least going by what AnandTech has, the XT1095 (Pure Edition) and the XT1097 (AT&T) are identical and are both the IHDT56QA1. That would suggest that it is just a mistake on Motorola's website that the Pure Edition is shown to be lacking some of the LTE frequencies of the AT&T version. Or perhaps, as some have suggested, the hardware is identical, but some bands are inexplicably disabled in the firmware.

The IHDT56QA3 (XT1092), which has frequencies both for Sprint and for T-Mobile was initially listed in the AnandTech review as a Sprint model. But after my email the author changed that to a "?". He said to me that in the reviewer's guide the IHDT56QA2 (Verizon) and IHDT56QA3 are said to be the same hardware, but there is no carrier information given about the IHDT56QA3. So maybe the IHDT56QA3 (XT1092) is for Europe or somewhere else in the world, as some have suggested. I wonder if Motorola submitted for approval to the FCC a variant for Sprint, but then no deal was made with Sprint, so it just won't ever exist (but that's just speculation on my part).

I also think there's a reasonable chance that the IHDT56QA3 (XT1092) is the Nexus X. That would explain it's Sprint, AT&T, T-Mobile friendly radios and the fact that it's identity is kept mysterious in the reviewer's guide. There was a leak yesterday suggesting that the new Nexus device has basically the exact same design as the Moto X (but a bigger screen--blech).

As it stands, if Motorola has a variant that covers both Sprint frequencies and covers T-Mobile frequenices better than the Pure Edition and if it has already been approved by the FCC, it is beyond my comprehension why they don't just sell that as the Pure Edition. It would be better for T-Mobile users, it would be fine for AT&T also, and it could pick up some Sprint customers, even if Sprint is not going to sell a subsidized version. Maybe Motorola just doesn't like money?

Unfortunately, this clarifies some of the nomenclature, but doesn't really answer a lot of the questions we all have in this thread. I still think, for those who want to use the Moto X on T-Mobile it is better to take a wait and see approach, for the next couple months, than to leap on the current Pure Edition. It seems a little unlikely, but there might in the future be a better variant for use on T-Mobile (even if it's a variant for some other part of the world).