Switched 3 lines to Tmobile, and since added 3 more devices.  Extremely pleased, and that I am paying less for 5 devices now than I did for 2 or 3 with Sprint.

 

LTE with very fast speeds in most places I travel.  From NH down to Virginia, you will not have any issues.

 

Coverage down south can be problematic, particularly on the data side.  On the whole, if you stay within a large metro area, you will not have any issues.

We have been T-Mobile customers for the past 13 yrs. Over the years coverage has gotten better and their cs has been good. However, since my son upgraded to an LG L9 several months ago the coverage at work and home has been very poor. It wasn't the best with his previous galaxy 4 but better than now. He lives on the Ewing/Hopewell border and works close to home. Except for this, we are generally pleased with them.

That can happen with certain devices...depending how/where LG has their antenna placement, the way one holds their phone can affect signal strength, crazy but true.