The people posting positive things about "Chamberlain Research Consultants" are shills for the company, exactly the sort of thing you'd expect from SCAMMERS.

This is a telemarketing operation making unsolicited calls, refusing to honor the spirit of the Do Not Call regulations and they do not maintain a no-call list of their own. They will harass you, and refuse to stop harassing you.

I just found out that survey research is exempt from the Do Not Call list.  However, if you ask a research firm to remove your name from their list they will.

Quote from FTC website:
http://www.ftc.gov/bcp/edu/pubs/consumer/alerts/alt107.shtm:

"calls from or on behalf of political organizations, charities, and telephone surveyors would still be permitted, as would calls from companies with which you have an existing business relationship, or those to whom you’ve provided express agreement in writing to receive their calls. However, if you ask a company with which you have an existing business relationship to place your number on its own do-not-call list, it must honor your request.  You should keep a record of the date you make the request."