As someone with a great deal of first hand familiarity with the Sprint network - in the western region, the last network upgrade was a forklift upgrade - out went the ALU (alcatel-lucent) hardware, and in went brand new shiny Samsung hardware, with brand new shiny tower top radios, and brand new shiny antennas, all connected over a fiber backhaul.

In my market, even the 1x network is hugely improved (as well as EV-DO) - I also take issue with you using 1x fallback to imply that on the sprint network there is another way to make phone calls other than 1x - there is no VoLTE footprint on the sprint network.