Their spread is usually 1/2 cents & very liquid. I used to use market orders for entry & exit with smart routing until I had my executions way out of lines. After closed look & have found many cases in the execution in time & sales like that. Why the bid & ask all of sudden jumped for only 1 trade? Is it the trick of mm to trap trader w/ lousy executions at reversals? Now I enter limit oder w/ 2 cents above offer to exit. What is the better way of order to prevent the split second moving traps & get executed in the same time?