MobileX has followed-up twice asking if there have been any other issues beyond the voicemail hiccup. In my opinion, being proactive during a beta is a good sign.
As mentioned earlier in the topic, I’m refraining from running speed tests until closer to the end of my 10-day learning period. So far, for my admittedly modest use, the cell data provided by MobileX has been entirely adequate.
Cell data on the custom plan is, according to the Internet, priority data on Verizon’s network. The “fake unlimited” plans are deprioritized.