A usual part of any ICO is it's disclaimer that the project is not a guarantee of a fool proof profit. In fact, most ICOs does not explicitly tell people to invest, rather, they ask people to support and believe in their agendas.
As to your question if it is the good time to invest in an ICO, the answer is really in your hands. Have you found an ICO that you believe in? If so, go ahead by all means, otherwise, it would be best to keep researching and trying to learn more of what their project is all about before doing so.
You don't need to spend much time to find the nature of ICO. Currently is still the good time for ICO investment. But, if you want to have a profir like x10 x100, you should to be careful. Almost the ICO project promised that profit are the scam project. Because real projects are wanting to develop their product and release as soon as possible. Instead of focus in the value, the exchange to be listing, real project usually focus for development.