Been using various Needl products for over a year and have been extremely impressed with the granularity with which you can drill down... No more undisclosed data sampling!!
I used Needl to help understand factors impacting conversion rate on a classified automotive platform. The insights directly helped shape keyword buying and content strategies. It's ability to home in on supply and demand attributes also helps inform the sales process - providing real time examples of user demand.
Too much to say and too many layers that you can get into to even get close to describing it. - get recommend you get in-touch with them they will describe it much better than I can