I have been using them for a year now and they have been very good to work with. Although I am not a day trader and typically hold my positions for at least a week. They are also have great option calculators to plan for "what if" scenarios. They are a discount broker without any frills. Their charting package leaves much to be desired, But I use a different service for charting anyway. I would recomend them for the kind of trading I do, but if you need all the tools, and streaming quotes, I think there are better brokers out there. TradeKing does have live streaming quotes, but you must place at least 40 trades per month. With that being said, the platform is very user friendly and intuitive. I have not experienced any problems.