There are a few good things about IEX, especially the fact that you can get their real-time feed for free. The downside is that it isn't really free as you need

There are a few good things about IEX, especially the fact that you can get their real-time feed for free. The downside is that it isn't really free as you need to have servers that IEX auditors can visit at any given time, which means you need to have a co-location at the minimum, which isn't cheap. Which brings me back to the point that I have no clue how one can offer supposed real-time data on options for free.