That works for S9s as well, that's how I've been testing and tracking around here recently. Their PCIs around here are like AT&Ts, a mess. At least most T-Mobile sites have at most 2 GCIs for now until M-MIMO b41 starts coming online. Sent from my SM-G965U using Tapatalk
Honestly I haven’t roamed on T-Mobile yet at least here in Charlottesville. Considering that Both T-Mobile/Sprint have very well got the entire city covered atm. Hopefully once they start transitioning things over it will be more likely.