+1 re negotiating TOS' rates. also remember to take into account other fees like ib's modify/cancel fee. yes you can get credited on this for PART of the fee but it can still add up if you modify/cancel orders a lot. i know i do this alot (and pls don't say "if you always hit the bid/ask you'd never have any fees
). the total package (all fees, execution, security of funds,etc) should be taken into account when looking at a broker.