IEO could be the new thing today, the only problem is that they are sold out the minute it has been officially released. Of course we can control the market and we really don't know what's going to happen.
Agree basically IEO and ICO is almost same. in IEO, Exchanger has the entire power to manipulate the price and the coins. That's why the coins can be sold in just a second.
Just like IEO, ICO is more risky to invest because it's a new project and we don't know what they do on behind. As the saying goes "We can't trust people on the first meet."