Sprint does Roam onto US CELLULAR LTE which I believe uses band 12. Tmobile coverage is close to Sprint So Sprint wouldnt do much roaming onto them .Yes their are spots where Tmobile covers that sprint does not but, its small. I wish sprint could get their hands on their Native 700 mhz. Can say for sure no LTE on VZW. Also Theres no band 17 support on Sprint phones only band 2,4,5,12.