How can the OP be unaware that the Mifi is connecting to the same Verizonwireless tower regardless of whether the account is through Verizon directly or through their reseller, Millenicom. Why post a rant that only shows how stupid you are?
We used Verizonwireless and with 3G we had lots of problems. 4G made a great deal of difference and we switched to Millenicom to get both a better rate and to avoid overcharges from Verizonwireless.
A great many people on the Verizonwireless website's forum were reporting bills with charges for excessive use of $300 or more and no success in getting Verizon to explain why as soon as they switched to 4G their usage apparently increased 5 fold when their online activities had not changed.
Millenicom resells service with either Sprint or Verizon tower access. Verizon has more towers and better coverage in the USA than any other provider. There are online tower maps so you can determine which provider has leased space on the tower closest to your house.