Just as an example, I don't know if the accusations are well founded, this Exchange has two pending scam accusations:
https://bitcointalk.org/index.php?topic=5088254.0
https://bitcointalk.org/index.php?topic=5109812.0

And some negative feedback https://bitcointalk.org/index.php?action=profile;u=252173

However, they still post their announces on more than a local board free of any tag to warn potential victims.
German
https://bitcointalk.org/index.php?topic=5130668.0
Spanish
https://bitcointalk.org/index.php?topic=5125188.0