Well, I'm sitting here northwest of Pittsburgh near the Ohio border using a v60, and i can tell you that Sprint has coverage where T-Mobile wasn't even trying.
One infuriating thing is that this phone isn't currently working properly when it has to use Sprint B26, which is pretty much all the time because it connects to 800 as well when using 1900 and 2500 most of the time.
Phone loses its mind: LTE flag on, VoLTE flag on, VoLTE flag off, Roaming flag on, radio resets and we start all over.
It gets stuck in this loop sometimes even when returning to T-Mobile coverage.
Android Auto connects and disconnects every time the radio resets.
It's infuriating, and all I can get Sprint to admit to is an "outage" that's supposed to be fixed by a date that keeps getting pushed back.