The trustworthy ICO rating websites are limited, I only trust ICObench and ICOholder, and even after checking the ratings there, I make an additional research to avoid all the risks before investing, or joining the bounty campaign. There is always a risk involved with the ICO investments so we have to study carefully the projects before the investment.
You cant totally call them to be trustworthy fully even though listing of ico is convincing but not totally a valid thing or sure thing to be followed if you are an investor.Additional research should really be needed if you are having a second thoughts on joining up. Our knowledge and research skills will vary and i agree on some dude mention on here that some of them are just shilling out a project because they had been paid and do their job. This is why further research is recommended anytime no matter how popular they are.