Hi - I was looking into IB a while back and would agree that their commission structure is great for smaller positions but if you take larger positions it can be quite a bit nore than the flat fee at other brokers like Scottrade, Ameritrade, etc. One thing I found very interesting at IB, when looking over their "fees and rates" page, was that when you are short, they apparently credit your account with interest on the proceeds of the short sale. Nice - I have never seen another broker do that!
sjd
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