I personally think that all the survey routers/senders are notorious and only qualify the panelists whom they have close relationship. They perhaps do not have expertise to choose a right panelist.
To name a few of that type of unethical and notorious survey routers/senders are Sample Cube, Samplicio.us, Yuno Survey, Your survey etc. They have become nightmares and I don't know when we the panelists would be free from their dirty claws.