The only time you get great coverage with T-Mobile is when you're in a metropolitan city. Other than that, go to verizon. T-mobile does a good job of sucking people in with the really low rate plans and then the cell phones being really cheap too. some are good and some are bad. just stay away from any samsung phone.
they keep on pushing the hotspots at home, but if you're only experiencing problems in your home then that's cool, problem solved with wi-fi calling. but if you drop it everywhere else and don't have wi-fi coverage in that area, then it sucks... i heard from a friend of mine that was a T-Mobile employee that they are not going to waive anymore ETF fees because of the hot spots at home being available now.