There isn't really much difference between the both of them except that one is being launched directly from the exchange and the other is not. Lots of projects these days are opting IEO these days but does that make any difference?? And does it mean that they are not going to have problem like lack of funds any longer?? Cause one thing I'm very sure is that people are able to sell their tokens once the project has kicked off, so what's the difference?? The price can still drop and lose value overnight. The only thing that IEO can be more safe than ICO cause most of them will be legit I guess.