I've been using Net 10 for 5 years now.

 

Price works out exactly like this:

 

$30 gets you 60 days or 300 minutes whichever comes first (you can leave the phone off, charge lasts 2 weeks without talking)

$60 gets you 120 days or 600 minutes whichever comes first (you can leave the phone off, charge lasts 2 weeks without talking)

 

Simple enough? It's $15 a month with no taxes and no fees. That covers the cost of the phone (which is $30 and comes with 300 minutes)