I agree that it's a tough choice between ICOs and IEOs - IEOs have already been verified by the exchange and there's guaranteed listing so you're sure the project won't collapse, but ICOs may be cheaper and are also in the process of listing themselves on an exchange. It also depends on how much you're investing - if you're testing a small amount, I think there is no harm in trying ICOs as well. One good example of an ICO is BCART (BlockCart), an AI and blockchain enabled online shopping software solution. It's a Korean project that's been incorporated in Singapore. You could check it out here and their Airdrop/Bounty is live for two more weeks I think! As always though, it's important to do DD and as much research as possible before you buy into anything and talking to the projects' members/admin etc. will help

In terms of IEOs, I think it may not be 100% guaranteed as well because even if the project is authentic, it may not do well on the exchange either - personally I'd look at Binance like some of the other commentors have highlighted!