We have MVNO providers that offer a pretty low price for similar. Simple Mobile has a $40/month plan that is unlimited voice, unlimited text, and unlimited 3G data. For $60/month you get the same, except unlimited 4G data (it's HSPA+ on T-Mobile). Straight Talk offers unlimited voice, unlimited text, and unlimited 3G data for $45/month on T-Mobile or AT&T and you can bring your own phone.
So, why do I still have Verizon and am paying $156/month for two Android phones with "unlimited" data, 700 minutes shared on a family plan, and 500 text messages on each line? I have no idea. I think it's the fear of losing my "unlimited" data plan on Verizon that I've been grandfathered into even though neither my wife or I use more than 500MB of data a month. I could easily be saving $70-$80/month switching to a prepaid provider. I'm actually looking forward to the day when Verizon pulls the same throttling thing AT&T did on their grandfathered data customers because I won't even think twice about switching providers at that point to save money.