My SERO 500-P is the original plan. The 50.00 is including the smartphone fee. When It came out it was a $30 plan. Then if you wanted a fancy phone you had to change to the SERO-P at 40 and then you pay the $10.00 Premium data fee.
I get 500 minutes BUT any call to ANY CELL is FREE and UNLIMITED AND nights and weekends are free!
it's was funny last night I tried to explain this to another poster on Sprints official community and my post was rejected and I was told that you are not allowed to discuss SERO in Detail!
WOW!