Nowsaday, I don't think there is any ICO worth to invest anymore. I had so many bad ones lately. Better off purchase them after they released at the exchanges.
Risk is always involved when investing in ICOs. Try to assess the risk accompanied by those certain ICOs by doing some thorough research about it. It is always better if you do some extensive background check on its Dev Team (past works, reputation within the forum, etc.) And lastly, don't put all your money into a single ICO. Diversify your investment and study its risk/reward ratio.