My understanding is that this model will work on T-Mobile. You will get LTE speeds, but not on band 12. May or may not make a difference depending on the status of band 12 deployment in your area. But you should get LTE speeds without it just fine.
I am on T-Mobile in Raleigh and it works flawlessly. The device doesn't have band 12 support, so if you are in an area that has that spectrum you may want to go with the full sized Z3 D6616. In my area there is no band 12 from T-mobile (and there likely won't be for 12-24 months) so I wasn't concerned. Also see https://sites.google.com/site/cellularbinder/t-mobile-700a-spectrum