There's a great article over at bizcommunity.com outlining the downside of internal market research. Having led internal market insights and analytics teams in my past, I agree with many of the points raised in the article.
Their summary hits the nail on the head for me. They recommend having a good mix of research suppliers. I can't stress enough how valuable I've found my partners at a variety of research vendors over the years in reviewing my work, offering suggestions, and generally keeping me grounded. It's not a matter of pitting one agency against another. To me, it's about establishing relationships and working together. There have been numerous times when I've called a research partner not to bid for a project, but just to grab 15 minutes of their time to bounce around ideas. And I'm humbled by the fact that they've done the same with me.
This reciprocity not only solves for the immediate need of assistance, but it helps both sides determine how best to work with each other, forming the basis for a long standing and mutually profitable relationship.