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.
IEOS still profitable than ICO because IEO listing on exchange market faster than ICOs and investor never hold coin for long time like ICO coin, with IEO investment investor can sell after IEO finished one days. IEO have big exchange market for listing and ICOs do not have which one exchange market for listing after ICO sale ended and the ICO team looking which one exchange market have less payment fee.