Just wanna say: you absolutely can judge people on very few things. You owe nobody the benefit of the doubt. If someone gives you a hinkey feeling, you can openly write that person off. You can make snap judgements based on first impressions and as long as you are very specific about why? Go right ahead.
A lot of icky predatory white boys will tell you that's irrational, but I don't plan to lower my standards to accommodate their mediocrity. Neither should you.