I have had an account with them for 7 years. I opened the account for trading size in stocks. When I am hitting the bid ask, the order fills seem to be as fast and good as for any of my other accounts. I do not use Ameritrade for orders of less than about 3000 shares due to the commission cost. The cash, when not in use, sweeps into a Reserve Fund. I would not want Ameritrade for my only broker (that tells what I think of them from an overall standpoint). If I could have only one account, it would not be Ameritrade. It would be IB.