Before investing in the new project, whether it be - ICO or IEO is necessary will study a lot of information. First of all it is necessary to look at team, good team - the key to success. It is also necessary to study and estimate whitepaper. It contains a lot of useful information!
Whether it ICO or IEO, we should keep making research before making investment. I am believe IEOs are good but now most exchangers doing IEOs and every investor must be hold a good project for long term