I think it's the same with everthing, sometimes you just have to loose money to learn sth. But it's always better to learn sth at first, and use others experience.
Nah, you shouldn't following other opinions because sometimes people just promoting their scam coins to help the dev collecting your money before dump their project. However, read and keep track your ICO are a way to make sure you do the right choice with following the trustworthy ICO.