If you're planning to use them on Tmobile, they usually only run on Edge speed. They force manufacturers to only put ATT radio bands.
LOL - T-Mo is the odd duck here using Band 4 AWS for H+ when for most other carriers Band 4 AWS is used for LTE...
In fact that is the cause of the refarming T-Mo is doing. Putting Band 4 to work as LTE and then putting H+ on 1900 where it is with most any other carrier using the same frequencies.
T-Mo was late rolling out H+ so they used the Band 4 the FCC put on auction for LTE rollouts to beef up their sagging H+ and are now coming behind themselves playing catchup.
1700 uplink / 2100 downlink as H+ capacity (which T-MoUS did and is now undoing) is the exception, not the rule. This situation has been becoming less common over the last 2 years.
If you want to point a finger at AT&T for footdragging it would be the use of Band 17 LTE (700MHz blocks b/c) which is narrower than Band 12 LTE (700MHz blocks a/b/c) due to worry about bleed through from an adjacent HD Television broadcast spectrum hardly used in any markets. Now AT&T has to play catchup and move to Band 12 without abandoning their customers they pushed Band 17 LTE handsets to.
The proliferation of very cost effective AT&T mvno carriers makes these frequency concerns a non-issue for many users.