Thanks for the reply! So it appears as though Ally is a bit "faster" than TD Ameritrade since TDA quotes come in bursts. So if you were to choose between Ally, Tradier or TDA, which one would provide the fastest quotes (all other things being equal). Does enabling something called API have anything to do with the speed of quotes? Finally, out of curiosity, why did you use Tradier as your data source in the YouTube video? Thanks!