Do some Google searches and see if you can find out about what people prefer in your area. People can talk all they want about "AT&T drops calls" or "Verizon's speed sucks" etc. etc. The truth is that it's extremely dependent on where you are. So do some research and see what people generally have to say about their coverage and speeds in your area.
I'm in Michigan, and I'm getting between 4-5 Mbps on AT&T. I occasionally have a dropped call, but not often enough to bother me. But that doesn't help you at all because you're in FL.
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Just because AT&T was bad for you doesn't mean it is for everyone. And not everyone travels a lot. If you only travel once or twice a year, you should get coverage based on what works in YOUR area. If you travel every week, then you'd have a lot more research to do.
thanks!!