I've alternated between Cingular/AT&T and T-Mobile. First cell phone was Cingular, then second was T-Mobile. Got my iPhone 3G when they were still AT&T exclusive, then switched back to T-Mobile with my iPhone 7 because AT&T kept jacking up the price of our grandfathered unlimited data plan and making sure we couldn't use any of the cool new features. T-Mobile has so far honored their word, my old plan is still priced the same and has the same features as the day I signed up with them. I am on wifi most of the time so I really don't know how often I have 5GUC, I'm also in pretty bad areas for signal/speed for a lot of my commute (subway and train through very densely populated areas) so it's not really representative. At home, if I turn off wifi I have 5GUC, but for some reason it's ridiculously slow, like 2Mb/s download and 0.1Mb/s upload. It's been like this for years, something is just not right with my local tower. Doesn't really bug me since I have wifi and wifi calling works great.