I know just2trade will match any deal. Lowtrade offers $2.5, that is before just2trade came into business. Ameritrade offers $5 Apex trades. Not sure about scottrade, etrade, IB. Please list your negotiated retail rate and how you talked them to lower your rate.
Way back when we were retail, our rate was 2.2 mils/share with a max ticket of $5.00 plus ECN rebate/minus ECN charges plus SEC. Now we are self clearing and get much much better rates.