As you know IEO trend is growing but i feel IEO is profitable only for those who invested in token sale but who have purchased altcoin after launched they suffer loss majority of the investors ,as the BTT and some other altcoin examples of IEO.
I think the IEO and ICO are almost the same. However, IEOs are censored projects and they are listed on the exchange so the IEO is much more profitable than the ICO. And I will trust to invest in IEO because currently there are very few IEO scam so you can trust to invest in them.