We've had AT&T for years and we are happy with them. My husband is on the road a lot and coverage is vital. The only times we have issues is when he is going through much smaller towns and there are not as many towers. That is not often so for the majority of the time, we are covered.
As far as rates, I have no idea how to help. We all 3 have IPhones. My daughter is o my plan with me and by the time I pay for unlimited texting, etc (which will soon go away), and the 2 data plans, our bill is $191 per month.
Hubby's plan has more minutes included, texting and data plan and his bill runs $171 a month.
I do know they have better plans, ours is higher due to the unlimited texting and IPhone data plans.
Good luck.