If ICO wasnt been plague by scammers acts ICO will way better than IEO, ICOs are programmed to run on the projects very own website and no any third party involvement at all so any fund raised will go directly to the dev or project team, no loss of funds to scam exchanges,after some successful IEO fund raise on some exchanges they dont bother to send the funds back to the project teams
the party would have been going on still if those ICO were managed properly, there were escrows before they take them out of the picture. that's when they started groupoing a lot of these team doing ICO without escrows. there were some that ended quite good though. IEO is just going to make all these worse if all these small exchanges never been heard of are going to do IEO for some projects.