Perhaps the broker's datafeed won't run a particular software you are using, maybe you feel better having a backup, where I live I use to have problems getting esignal to run and IQfeed seemed faster and reliable. The broker might not be pumping out all the data whereas exchange or CQG gives much more ticks than others. Listen, trading is a business, and you get what you pay for in most businesses, this no different. IB's data are flash quotes.