Somewhat-Reticent Some complaints suggest Verizon pranking this wannabe third-party middle-ware vendor.
Not sure what you are referring to.
US Mobile is a well-established MVNO, and has longtime used Verizon network and also T-Mobile.
Their new addition is AT&T.
US Mobile does not use Verizon's name in its marketing, but offers "Warp" (previously "Super LTE") branded service on the Verizon Wireless network. They also offer the T-Mobile network branded as "Light Speed" (previously "GSM 5G" and "GSM LTE"), and AT&T network support as "Dark Star".
I've been a US Mobile customer for years (currently for their Verizon service).
While every company generates some complaints, they seem very good overall and my interactions with customer support have been quick and efficient.
(For comparison, I also have accounts with Red Pocket (AT&T and also T-Mobile), Tracfone (Verizon), and directly with T-Mobile).
One nice thing about multiple services (which really do not cost that much) and dual-SIM phone is being to check coverage in real life.
I find overall that T-Mobile has gotten better than it used to be, but still falls behind on coverage inside buildings. That's not done with a 5G phone however.
Outdoors things can vary widely but here in NJ, Verizon does seem best overall, AT&T second, and T-Mobile third (even with a direct T-Mobile account).
US Mobile has been around for 10 years.
Originally founded by an immigrant student who found a hard time passing the credit checks of the big companies, and who built his business on helping people in similar situations.