T-mobile is the best bang for your buck. They are rolling out 700mhz spectrum this year to address their historically poor indoor reception. LTE is expanding VERY quickly and it's fast fast fast.
I pay $30/mo for 5GB, unlimited text, 100minutes (which can be topped up). Unbeatable as far as I know.
I agree, I have that plan too, and if you have an unlocked phone/don't need the payment plan/subsidy, that's the very best deal out there. Even if you have to go over on the minutes and pay extra it's still cheaper.