Why would people still invest in something with a much higher risk than IEO? Not that IEO is perfect as it still has it's risks, but is way much better than ICO... so....
ICO and IEO are almost the same, save for the platform used for the coin offering. IEO is basically another way of coin offering just like ICO. It is just that it is being offered in an exchange. What investors should be looking into is not the way the coin is being offered but the project details itself. Whether a project is offered in an ICO or IEO does not count much. What counts is that it is offering a new idea and that they have a great product that is practical to as many people as possible.
Unlike in ICO's where scammers are actually increased their numbers and they totally doomed everything about this coin offering, becoming the reason for investors to avoid ICO and do something better.
We can consider IEO to be safe as of now, they become more successful compared to ICO. The way how IEO's run is totally different because it is using some popular exchange to run their coin offering.