Why in the world would you trade listed stocks? Nasdaq,because of its volatility, is great for daytrading.The fills are quicker,the playing field is more level,and you are not competing with floor brokers for fills,who always get the good fills,especially when the market is moving.Level 2 can be used to determine who is buying,selling and refreshing their quotes.If you see an ECN bid or offer,you know that as long as it's there,you can hit it or take it.All you see on listed stocks is the best bid and offer,and lots of fake sizes that when you try to hit the bid or take the offer,you get offered there or bid there,without any stock trading.Stick with Nasdaq,much more money to be made on it.
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