There's many ICO Rating websites, and most give unbiased ratings and reviews. You should be able trust their rating score because at the end of the day you can review their rating by adding a post below the ICO they have rated
You should not trust any of their rating score because you said that they were biased . instead, you can just review again the ico and give your own honest feedback and you can compare your own feedback to other feedback to see if what is right or wrong .
In my case i do not easily believe any ico rating because i am alaready aware that majority of ico are verry unrealistic .
Ratings are nothing and wont make them look legit.