If the indicator is investor interest, I believe that IEO is better than ICO. Moreover, lately many ICOs have been a scam, not being listed on the market even though a lot of time has passed. That is why the IEO strategy is more in demand by investors today. However, it also does not guarantee that all IEOs will succeed. It depends on many things, such as exchange, market interest, project strength, marketing strategies, etc.
IEO has always been of particular interest to many new investors because they can know for sure which exchange will list that coin and if it is a top exchange, the project will have a high rate of success. I have observed a number of IEO projects at small exchanges and most of them are always abandoned so before investing in IEO it is necessary to consider carefully and should choose a good exchange to participation . The best advice is to choose Binance, Gate, Okex, Huobi, Zb these are the exchange you can trust.
It seems that only platforms like binance, okex, houbi are safe with IEO. However, I do not think joining the IEO of these platforms is easy. With Binance, you need to hold BNB for 15 days to receive a ticket, but the rate is very low from 2-10%, if the value of BNB dump after IEO and the currency you buy IEO has an ROI of less than 200%, I think there will be no profit.