Traveling a lot usually works best with Verizon. As you said there is no perfect carrier but Verizon does have good coverage.
I likewise have traveled a lot through out my business working life. I tried all of the carriers and finally decided that I would have to try out Verizon. I left them until last because they were "always" more expensive than anyone else.
But, when I saw that VZW does indeed offer the best coverage of them all, I stayed with them. I have been with them now for about 20 years and don't intend to jump ship. I know what to expect, and I can threaten them once in a while with leaving when my phones all go off contract.... They have always thrown me a nice juicy bone to salve the wounds financially.
When you are on "auto-pay" direct to a checking account (not a CC) and have never missed a payment, you get preferential treatment once in a while.
. sort of like when AT&T (my DSL provider) called me up a while back and said, "hey, we see you have DirecTV" how would you like to save some money? I kept telling them 'no' but after about six months, they made the deal so sweet I went for it.... they merged my DTV billing onto my AT&T internet billing and knocked off a bunch of clams for more than a year... 15 months IIRC.
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