Pay attention to time frames. Trading signals do not work well for strategies such as scalping. By the time you receive the signal, the scalping opportunity has already come and gone. The best signals are probably on daily charts. Maybe 4 hours. Because the signal algorithm has more data to work with than say a 15 minute span. Besides, you need to get the signal, and apply it. AFTER you verify that the trade is viable. Based on your own analysis. That takes time, and the signal could have been well in progress by then.