I really don't see why it is that you think that if you don't have public wifi then you wouldn't use an MB. The MagicBox is a repeater for Sprint's network requiring essential zero exposure or expenditure for the retail provider beyond electricity. It is also zero maintenance or setup. It's a highly superior solution in my view.
Anyone having issues with the messages app receiving late or not sending messages? Received a few pics and see the attachment downloading but app closes unexpectedly. This happens with Sprint to Sprint phones (Pixel to iPhone) as well with AT&T numbers
Speaking of WiFi calling being inconsistent. Do you ever have issues when receiving a call? Sometimes when receiving calls with WiFi calling enabled and WiFi is on but not connected to a network. The phone calls are choppy and I sound like a chipmunk to people on the other side of the call.