Have had very little need over the years to ask for help. We have made use of the "free" intl roaming feature in about 14 countries the past 3 years or so. (Since the day it took effect.) Have been w. TM since they came to the U.S. when they took over Omnipoint-Voicestream.
We have phones w. Miami (2) and California(3) phone numbers and one in Seattle. We are on the grandfathered Simple Choice plan. Most lines use under 500mb of data. Rarely hit the 2Gb mark.