IEX only adds 350 usec in delay.  I&#x27;d also add that if you just read Flash Boys you probably got a very incorrect view of what high frequency trading is all about and particular what cross exchange market making is about.<p>You should read <a href="http:&#x2F;&#x2F;www.amazon.com&#x2F;Flash-Boys-Insiders-Perspective-High-Frequency-ebook&#x2F;dp&#x2F;B00P0QI2M2" rel="nofollow">http:&#x2F;&#x2F;www.amazon.com&#x2F;Flash-Boys-Insiders-Perspective-High-F...</a>.