I think you can never really calculate if less latency is better or worse. At least not if you buy/sell at market price. I trade the ES and I see many times that at the moment I buy or sell at the market, the price just went up or down 1 tick. You can never predict if the next tick will be up or down, an also not when that next tick will come. So you never know if you finally got the price you clicked on or another one. You can only be sure about the advantage of less latency if, when you enter the market, there will NEVER be a one tick move in the wrong direction. Only if you put an order in the market before it is touched you can try to see if the lower latency gave you an advantage. And even then it depends on where you are in the row with your order. I even think that your place in the row has more impact than the latency. As daytrader saving one tick would not really change my overall performance on the long term. If your profit or loss depends on the one tick you should stop trading and look for a better trading plan.