I have noticed over the years that a majority of the traders on this board pay retail commissions. I have attached a spreadsheet that clearly shows that if you average more than 50 sides(25 round turns) a day and pay IB rates which are $2.4 a side you should lease a seat at the CME, and open an account at a professional clearing firm.
http://www.cme.com/trading/mem/leaseprices.html
http://www.cme.com/clearing/clr/fees/lessememp1870.html
http://www.cme.com/trading/mem/leaseprices.html
http://www.cme.com/clearing/clr/fees/lessememp1870.html