I recently signed up for cash4forex as an introducing affiliate for MB trading (test driving them and FastBrokers), which gives me 25% of every commission back to me, and MB pays you for putting in limit orders, there could be positive trading fees with this arrangement. I just thought this might help out with your scalping strategy. Especially since you want an ECN for the spreads.
Check it out, and I will report back on seeing if cash4forex pays their portion of the commissions back through my trading…