Moto X Pure will get a range boost when it get’s 6.x update. Currently T-Mobile’s Band 12, 700Mhz is disabled in this phone, but fret no more! This is all coming from David Schuster, a senior director at Motorola, where he states on Google+:
4) As part of the Marshmallow release of the 2015 Moto X Pure Edition, LTE Band 12 is enabled for the T-Mobile network.
This was all hinted to in these discussions prior to this update: