If you're really unsure and doubtful then just wait for that certain token to be listed in exchange sites and who knows you can buy less than the ico price and that's the best bargain.

This is just like hitting two birds with one stone since you save yourself from getting scammed and you can buy more when people dump their token. Isn't that a best deal for now most especially with thr current situation of ico. It's hard to risk our hard earned money.