I'm always trying to catch dumps after coins get listed at exchanges. As a rule the price soon gets back to ICO price. It's good opportunity to make good profit!
Yes, I think that if ico seems legit and worth investing in, it's best to wait till it appears on at least one solid exchange website and then buy some coins. Investing in ico is too risky, because you have to put a lot of money in a project and you don't even know whether you will be able to at least get some of it back by selling the coins. I mean, there's always a chance it won't even appear on any exchange website, right? So I agree with you and the op on this ico matter.