What you think more profit, participate in IEO or wait after IEO and buy the token from exchanges?
Participating ieos are of course more profitable comparing to buying from exchanges. You can buy much cheaper from ieos. But you have to be sure about the project not to be scammed. Because you have to wait till they are listed.
Waiting is not a problem with IEO, the fact that it's called IEO, it will be listed after the sale and exchange guaranteed that.