I have been trading with IB for about 8 years. I like their TWS for futures and stocks but now that I have shifted primarily into trading SPY Options I have started having a number of problems. When I attempt to execute market orders I often find myself needing to hit Transmit a number of times before being filled. This delay of 2 to 5 seconds can be expensive. I generally have everything set to SMART but maybe selecting a specific exchange might be better. Suggestions appreciated. Ron